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101. Dynamic nuclear polarization at 40 kHz magic angle spinning

Author: Lyndon Emsley, Sachin Rama Chaudhari, Christian Reiter, Daniel L. Silverio, Pierrick Berruyer, Moreno Lelli, Christophe Copéret, Anne Lesage, Frank Engelke, David Gajan, Solid-State NMR Methods for Materials - Méthodes de RMN à l'état solide pour les matériaux, Institut des Sciences Analytiques (ISA), Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Bruker BioSpin GmbH, D-76287 Rheinstetten, Germany, affiliation inconnue, Department of Chemistry and Applied Biosciences [ETH Zürich], Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Magnetic Resonance Center, Università degli Studi di Firenze = University of Florence [Firenze] (UNIFI), and Ecole Polytechnique Fédérale de Lausanne (EPFL)
Subjects: 010405 organic chemistry, Chemistry, Analytical chemistry, General Physics and Astronomy, Nuclear magnetic resonance spectroscopy, Solid material, 010402 general chemistry, Polarization (waves), 01 natural sciences, NMR, 0104 chemical sciences, MAS, Dynamic nuclear polarization, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, magic angle spinning, Magic angle spinning, DNP, Physical and Theoretical Chemistry, Physics and Astronomy (all), Physical and Theoretical Chemistry, SOLID-STATE NMR, SN-BETA ZEOLITE, THEORETICAL ASPECTS, IRRADIATED POLYETHYLENES, CORRELATION SPECTROSCOPY, ABSOLUTE SENSITIVITY, NITROXIDE BIRADICALS, MAGNETIC-RESONANCE, MEMBRANE-PROTEINS, HIGH-FREQUENCY DNP, Spinning, Signal amplification, Coherence (physics)
Abstract: DNP-enhanced solid-state NMR spectroscopy under magic angle spinning (MAS) is rapidly developing into a powerful analytical tool to investigate the structure of a wide range of solid materials, because it provides unsurpassed sensitivity gains. Most developments and applications of DNP MAS NMR were so far reported at moderate spinning frequencies (up to 14 kHz using 3.2 mm rotors). Here, using a 1.3 mm MAS DNP probe operating at 18.8 T and ∼100 K, we show that signal amplification factors can be increased by up to a factor two when using smaller volume rotors as compared to 3.2 mm rotors, and report enhancements of around 60 over a range of sample spinning rates from 10 to 40 kHz. Spinning at 40 kHz is also shown to increase 29Si coherence lifetimes by a factor three as compared to 10 kHz, substantially increasing sensitivity in CPMG type experiments. The contribution of quenching effects to the overall sensitivity gain at very fast MAS is evaluated, and applications are reported on a functionalised mesostructured organic–inorganic material., Physical Chemistry Chemical Physics, 18 (15), ISSN:1463-9084, ISSN:1463-9076
Published: 2016
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102. Rational design of dinitroxide biradicals for efficient cross-effect dynamic nuclear polarization

Author: Gilles Casano, Dominik J. Kubicki, Martin Schwarzwälder, Claire Sauvée, Sébastien Abel, Lyndon Emsley, Maxim Yulikov, Aaron J. Rossini, Olivier Ouari, Paul Tordo, Gunnar Jeschke, Christophe Copéret, Anne Lesage, Karthikeyan Ganesan, Solid-State NMR Methods for Materials - Méthodes de RMN à l'état solide pour les matériaux, Institut des Sciences Analytiques (ISA), Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie Radicalaire (ICR), Aix Marseille Université (AMU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratory of Inorganic Chemistry, Association of Computer Electronics and Electrical Engineers (ACEEE), Institute of Doctors Engineers and Scientists, Ecole Polytechnique Fédérale de Lausanne (EPFL), Laboratory of Physical Chemistry, Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Structure et Réactivité des Espèces Paramagnétiques (SREP), Université de Provence - Aix-Marseille 1, Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Cross effect, 010405 organic chemistry, Chemistry, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Radical, Relaxation (NMR), Rational design, General Chemistry, Electron, 010402 general chemistry, 01 natural sciences, 7. Clean energy, 0104 chemical sciences, 3. Good health, Nuclear magnetic resonance, Chemical physics, Polarization (electrochemistry)
Abstract: A series of 37 dinitroxide biradicals have been prepared and their performance studied as polarizing agents in cross-effect DNP NMR experiments at 9.4 T and 100 K in 1,1,2,2-tetrachloroethane (TCE). We observe that in this regime the DNP performance is strongly correlated with the substituents on the polarizing agents, and electron and nuclear spin relaxation times, with longer relaxation times leading to better enhancements. We also observe that deuteration of the radicals generally leads to better DNP enhancement but with longer build-up time. One of the new radicals introduced here provides the best performance obtained so far under these conditions. ISSN:2041-6520 ISSN:2041-6539
Published: 2016
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103. Predictive morphology, stoichiometry and structure of surface species in supported Ru nanoparticles under H-2 and CO atmospheres from combined experimental and DFT studies

Author: Christophe Copéret, Karol Furman, Anne Lesage, David Gajan, Fabio H. Ribeiro, M. Cem Akatay, Aleix Comas-Vives, Department of Chemistry and Applied Biosciences [ETH Zürich], Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Solid-State NMR Methods for Materials - Méthodes de RMN à l'état solide pour les matériaux, Institut des Sciences Analytiques (ISA), Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Purdue University [West Lafayette], and We thank the Swiss National Foundation for founding (SNF project number 200021_134775/1 Controlled Surface Chemistry for Catalyst Design and Ambizione project PZ00P2_148059)
Subjects: Materials science, General Physics and Astronomy, Infrared spectroscopy, Nanoparticle, Nanotechnology, 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, 0104 chemical sciences, Catalysis, Adsorption, Chemical engineering, Ab initio quantum chemistry methods, Chemisorption, Methanation, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, Physical and Theoretical Chemistry, 0210 nano-technology, Stoichiometry
Abstract: We are also grateful to Frank Krumeich and Emma Oakton for electron microscopy images, obtained on the ScopeM platform and to Maxence Valla for assistance with the NMR experiments. In addition, we are thankful to GLANTREO Ltd (Ireland) especially Dr John Hanrahan for providing SiO2-spheres support. We acknowledge the support from the Swiss National Supercomputing Center for computational resources.; International audience; Further understanding of the chemisorption properties towards CO and H-2 on silica-supported Ru nanoparticles is crucial in order to rationalize their high activity towards methanation, Fischer Tropsch and Water Gas Shift reactions. Ru nanoparticles having the same chemisorption properties towards CO and H-2 were synthesized on different silica-based supports in order to combine various analytical techniques and obtain complimentary detailed information on their structure; while silica spheres were used in order to obtain high-resolution TEM images of the Ru nanoparticles, high surface area silica-based material (SBA) allowed CO chemisorption to be monitored by C-13 NMR spectroscopy. In addition, a model of the hcp-based Ru nanoparticles observed by HR-TEM was used to predict by ab initio calculations the CO and H-2 coverages on the Ru nanoparticle under different conditions of interest in catalysis. For both adsorbates we show and quantify how the adsorption properties of the nanoparticle differ from the commonly used slab models. For the case of CO we show how the top, bridge and hollow sites can be present on the Ru nanoparticle, providing a description at atomistic level in good agreement with the IR spectroscopy measurements.
Published: 2016
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104. High-resolution NMR of hydrogen in organic solids by DNP enhanced natural abundance deuterium spectroscopy

Author: Anne Lesage, Lyndon Emsley, Aaron J. Rossini, Judith Schlagnitweit, Solid-State NMR Methods for Materials - Méthodes de RMN à l'état solide pour les matériaux, Institut des Sciences Analytiques (ISA), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Ecole Polytechnique Fédérale de Lausanne (EPFL), Prof. P. Tordo, Dr. O. Ouari and Dr. G. Casano (Aix-Marseille Universite) are thanked for supplying TEKPol. Financial support was from EQUIPEX contract ANR-10-EQPX-47-01, ERC Advanced Grant No. 320860 and the Ecole Polytechnique Federale de Lausanne. JS acknowledges support from a Schrodinger Fellowship J 3377-N28 from the Austrian Science Fund., ANR-10-EQPX-0047,SENS,RMN de Surface Exalté par Polarisation Dynamique Nucléaire(2010), and European Project
Subjects: Nuclear and High Energy Physics, Magnetic Resonance Spectroscopy, LINE-SHAPES, Analytical chemistry, Biophysics, 010402 general chemistry, 01 natural sciences, Biochemistry, Homonuclear molecule, Electromagnetic Fields, NMR spectroscopy, Theophylline, DYNAMIC-NUCLEAR-POLARIZATION, MAGNETIC-RESONANCE, Hydrocarbons, Chlorinated, Magic angle spinning, NANOPARTICLES, BIRADICALS, Histidine, [SDV.BBM.BC]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biochemistry [q-bio.BM], Spectroscopy, SN-BETA ZEOLITE, Ethane, Glycylglycine, 010405 organic chemistry, Chemistry, Chemical shift, Hyper-polarization, Temperature, Nuclear magnetic resonance spectroscopy, Condensed Matter Physics, Deuterium, Tetrachloroethane, 0104 chemical sciences, NMR spectra database, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, STATE NMR, MAS NMR, Indicators and Reagents, CHEMICAL-SHIFTS, BACTERIOPHAGE, Hydrogen
Abstract: We demonstrate that high field (9.4T) dynamic nuclear polarization (DNP) at cryogenic (similar to 100 K) sample temperatures enables the rapid acquisition of natural abundance H-1-H-2 cross-polarization magic angle spinning (CPMAS) solid-state NMR spectra of organic solids. Spectra were obtained by impregnating substrates with a solution of the stable DNP polarizing agent TEKPol in tetrachloroethane. Tetrachloroethane is a non-solvent for the solids, and the unmodified substrates are then polarized through spin diffusion. High quality natural abundance H-2 CPMAS spectra of histidine hydrochloride monohydrate, glycylglycine and theophylline were acquired in less than 2 h, providing direct access to hydrogen chemical shifts and quadrupolar couplings. The spectral resolution of the H-2 solid-state NMR spectra is comparable to that of H-1 spectra obtained with state of the art homonuclear decoupling techniques. (C) 2015 The Authors. Published by Elsevier Inc.
Published: 2015
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105. Iridium(I)/N-Heterocyclic Carbene Hybrid Materials: Surface Stabilization of Low-Valent Iridium Species for High Catalytic Hydrogenation Performance

Author: Delphine Crozet, Lénaic Leroux, Emmanuel Lacôte, Laurent Veyre, Lyndon Emsley, Iuliia Romanenko, Anne Lesage, Erwan Jeanneau, Christine Lucas, Chloé Thieuleux, David Gajan, R. Sayah, Laboratoire de Chimie, Catalyse, Polymères et Procédés, R 5265 (C2P2), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École supérieure de Chimie Physique Electronique de Lyon (CPE)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Solid-State NMR Methods for Materials - Méthodes de RMN à l'état solide pour les matériaux, Institut des Sciences Analytiques (ISA), Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Multimatériaux et Interfaces (LMI), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Ecole Polytechnique Fédérale de Lausanne (EPFL), We thank CNRS, CPE, Universite Claude Bernard Lyon 1, ANR (CFLOW-OM, NHCX), and Total (postdoctoral funding to D.C.) for financial support of this work. I.R. thanks CNRS/CPE for a doctoral stipend. TGIR RMN THC (FR 3050 CNRS) and ERC Advanced grant number 320860, are kindly acknowledged for the NMR characterizations. We thank the Centre Technologique des Microstructures (CT mu) for the TEM measurements., ANR-12-CDII-0002,CFLOW-OM,IMMOBILISATION DE CATALYSEURS DE METATHESE D'OLEFINES : APPLICATIONS EN PROCEDES BATCH & FLUX CONTINUS(2012), ANR-11-BS07-0008,NHCX,Chimie des complexes carbène-borane et carbène-silane(2011), European Project, Université de Lyon-Université de Lyon-École Supérieure de Chimie Physique Électronique de Lyon (CPE)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL)
Subjects: chemistry.chemical_element, Photochemistry, 7. Clean energy, Catalysis, chemistry.chemical_compound, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, ROUTE, Organic chemistry, Reactivity (chemistry), Iridium, supported catalysts, ENHANCED NMR-SPECTROSCOPY, ASYMMETRIC HYDROGENATION, Chemistry, Asymmetric hydrogenation, General Medicine, General Chemistry, Nuclear magnetic resonance spectroscopy, ENANTIOSELECTIVE HYDROGENATION, Mesoporous silica, iridium, ALKENE METATHESIS, REACTIVITY, carbenes, MESOPOROUS SILICA, solid-state structures, COMPLEXES, LIGANDS, hydrogenation, DYNAMIC NUCLEAR-POLARIZATION, Hybrid material, Carbene
Abstract: International audience; An Ir-I(NHC)-based hybrid material was prepared using a methodology which allowed the precise positioning and isolation of the Ir centers along the pore channels of a silica framework. The full characterization of the material by solid-state NMR spectroscopy showed that the supported Ir sites were stabilized by the silica surface, as low-coordinated single-site complexes. The material is extremely efficient for the hydrogenation of functional alkenes. The catalytic performance (TOF and TON) is one to two orders of magnitude higher than those of their molecular Ir analogues, and could be related to the prevention of the bimolecular deactivation of Ir complexes observed under homogeneous conditions.
Published: 2015
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106. Atomic Description of the Interface between Silica and Alumina in Aluminosilicates through Dynamic Nuclear Polarization Surface-Enhanced NMR Spectroscopy and First-Principles Calculations

Author: Céline Chizallet, Maxime Caillot, Aaron J. Rossini, Pascal Raybaud, Maxence Valla, Lyndon Emsley, Christophe Copéret, Jeroen A. van Bokhoven, Anne Lesage, Mathieu Digne, Alexandra Chaumonnot, Department of Chemistry and Applied Biosciences [ETH Zürich], Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Ecole Polytechnique Fédérale de Lausanne (EPFL), IFP Energies nouvelles (IFPEN), Solid-State NMR Methods for Materials - Méthodes de RMN à l'état solide pour les matériaux, Institut des Sciences Analytiques (ISA), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Paul Scherrer Institute (PSI), M.V. thanks the SNF foundation for financial support (Grant No. 200021_142600). This work was funded in part by the ERC Advanced Grant No. 320860 and SNF equipment grant (206021_150710)., and European Project
Subjects: AMORPHOUS SILICA, inorganic chemicals, Silicon, Industrial catalysts, chemistry.chemical_element, Biochemistry, complex mixtures, Catalysis, Article, BRONSTED ACID SITES, Colloid and Surface Chemistry, Aluminosilicate, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, MAGNETIC-RESONANCE, M-XYLENE ISOMERIZATION, GAMMA-ALUMINA, Organic chemistry, Polarization (electrochemistry), AL-27 NMR, SN-BETA ZEOLITE, INTEGER QUADRUPOLAR NUCLEI, technology, industry, and agriculture, General Chemistry, Nuclear magnetic resonance spectroscopy, equipment and supplies, Amorphous solid, SOLID-STATE NMR, RESOLUTION SI-29 NMR, Solid-state nuclear magnetic resonance, chemistry, Chemical engineering, Density functional theory
Abstract: Despite the widespread use of amorphous aluminosilicates (ASA) in various industrial catalysts, the nature of the interface between silica and alumina and the atomic structure of the catalytically active sites are still subject to debate. Here, by the use of dynamic nuclear polarization surface enhanced NMR spectroscopy (DNP SENS) and density functional theory (DFT) calculations, we show that on silica and alumina surfaces, molecular aluminum and silicon precursors are, respectively, preferentially grafted on sites that enable the formation of Al(IV) and Si(IV) interfacial sites. We also link the genesis of Brønsted acidity to the surface coverage of aluminum and silicon on silica and alumina, respectively., Journal of the American Chemical Society, 137 (33), ISSN:0002-7863, ISSN:1520-5126
Published: 2015
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107. Solid-State NMR of a Paramagnetic DIAD-FeII Catalyst: Sensitivity, Resolution Enhancement, and Structure-Based Assignments

Author: Charbel Roukoss, Christophe Copéret, Lyndon Emsley, Eberhardt Herdtweck, Eric Oldfield, Emile Kuntz, Gwendal Kervern, Jean Marie Basset, Yong Zhang, Guido Pintacuda, Anne Lesage, Sylvian Cadars, Laboratoire de Chimie - UMR5182 (LC), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Anorganisch-chemisches Institut, Technische Universität Munchen - Université Technique de Munich [Munich, Allemagne] (TUM), Laboratoire de Chimie, Catalyse, Polymères et Procédés, R 5265 (C2P2), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École Supérieure de Chimie Physique Électronique de Lyon (CPE)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Conditions Extrêmes et Matériaux : Haute Température et Irradiation (CEMHTI), Université d'Orléans (UO)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratory for Inorganic, Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon)-Institut de Chimie du CNRS (INC), Centre National de la Recherche Scientifique (CNRS)-École supérieure de Chimie Physique Electronique de Lyon (CPE)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)
Subjects: Magnetic Resonance Spectroscopy, Magic angle, Cations, Divalent, Carbon-13 NMR satellite, Iron, Analytical chemistry, Fluorine-19 NMR, Crystallography, X-Ray, 010402 general chemistry, 01 natural sciences, Biochemistry, Catalysis, Magnetics, Colloid and Surface Chemistry, Organometallic Compounds, Magic angle spinning, [CHIM]Chemical Sciences, ComputingMilieux_MISCELLANEOUS, Earth's field NMR, Carbon Isotopes, 010405 organic chemistry, Chemistry, General Chemistry, Nuclear magnetic resonance spectroscopy, Carbon-13 NMR, Deuterium, Carbon, 0104 chemical sciences, Solid-state nuclear magnetic resonance, Anisotropy, Quantum Theory, Spin Labels, Condensed Matter::Strongly Correlated Electrons, Protons, Algorithms
Abstract: A general protocol for the structural characterization of paramagnetic molecular solids using solid-state NMR is provided and illustrated by the characterization of a high-spin Fe(II) catalyst precursor. We show how good NMR performance can be obtained on a molecular powder sample at natural abundance by using very fast (30 kHz) magic angle spinning (MAS), even though the individual NMR resonances have highly anisotropic shifts and very short relaxation times. The results include the optimization of broadband heteronuclear (proton-carbon) recoupling sequences for polarization transfer; the observation of single or multiple quantum correlation spectra between coupled spins as a tool for removing the inhomogeneous bulk magnetic susceptibility (BMS) broadening; and the combination of NMR experiments and density functional theory calculations, to yield assignments.
Published: 2006
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108. Surface versus Molecular Siloxy Ligands in Well-Defined Olefin Metathesis Catalysts: [{(RO)3SiO}Mo(NAr)(CHtBu)(CH2tBu)]

Author: Anne Lesage, Christophe Copéret, Frédéric Blanc, Richard R. Schrock, Jean Thivolle-Cazat, Lyndon Emsley, Amritanshu Sinha, and Jean-Marie Basset
Subjects: Olefin metathesis, Web of science, chemistry.chemical_element, General Chemistry, General Medicine, Metathesis, Heterogeneous catalysis, Catalysis, chemistry.chemical_compound, chemistry, Molybdenum, Organic chemistry, Well-defined, Carbene
Abstract: Keywords: carbene ligands ; heterogeneous catalysis ; metathesis ; molybdenum Reference EPFL-ARTICLE-204411doi:10.1002/anie.200503205View record in Web of Science Record created on 2015-01-08, modified on 2017-12-03
Published: 2006
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109. Assigning powders to crystal structures by high-resolution1H–1H double quantum and1H–13C J-INEPT solid-state NMR spectroscopy and first principles computation. A case study of penicillin G

Author: Bénédicte Elena, Lyndon Emsley, Nicolas Mifsud, Chris J. Pickard, Anne Lesage, Laboratoire de Chimie - UMR5182 (LC), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon)-Institut de Chimie du CNRS (INC), University College of London [London] (UCL), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Models, Molecular, Proton, Molecular Conformation, General Physics and Astronomy, 010402 general chemistry, 01 natural sciences, Homonuclear molecule, Nuclear magnetic resonance, [CHIM]Chemical Sciences, Computer Simulation, Carbon Radioisotopes, Physical and Theoretical Chemistry, Nuclear Experiment, Spectroscopy, Nuclear Magnetic Resonance, Biomolecular, ComputingMilieux_MISCELLANEOUS, Crystallography, 010405 organic chemistry, Chemistry, Chemical shift, Penicillin G, Nuclear magnetic resonance spectroscopy, 0104 chemical sciences, NMR spectra database, Models, Chemical, Solid-state nuclear magnetic resonance, Quantum Theory, Physical chemistry, Powders, Protons, Algorithms, Heteronuclear single quantum coherence spectroscopy
Abstract: We show how powder samples at natural isotopic abundance can be assigned to crystal structures by using high-resolution proton and carbon-13 solid-state NMR spectra in combination with first principles calculations. Homonuclear proton double-quantum spectra in combination with through-bond proton-carbon HSQC spectra are used to assign the NMR spectra. We then show that the proton chemical shifts can be included in the process of assigning the spectra to a crystal structure using first principles calculations. The method is demonstrated on the K salt of penicillin G.
Published: 2006
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110. Detailed Structural Investigation of the Grafting of [Ta(CHtBu)(CH2tBu)3] and [Cp*TaMe4] on Silica Partially Dehydroxylated at 700 °C and the Activity of the Grafted Complexes toward Alkane Metathesis

Author: Jean Thivolle-Cazat, Jean-Marie Basset, Mathieu Chabanas, Lyndon Emsley, Glenn J. Sunley, E. Alessandra Quadrelli, Aimery De Mallmann, Christophe Coperet, Erwan Le Roux, Anne Lesage, Anne Baudouin, Wayne W. Lukens, University of Bergen (UiB), Laboratoire de Chimie, Catalyse, Polymères et Procédés, R 5265 (C2P2), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École supérieure de Chimie Physique Electronique de Lyon (CPE)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Chemical Sciences Division [LBNL Berkeley] (CSD), Lawrence Berkeley National Laboratory [Berkeley] (LBNL), Laboratoire de Chimie - UMR5182 (LC), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon)-Institut de Chimie du CNRS (INC), Ecole Polytech Fed Lausanne, Inst Sci & Ingn Chim, BCH, CH-1015 Lausanne, Switzerland, Université de Lyon-Université de Lyon-École Supérieure de Chimie Physique Électronique de Lyon (CPE)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Agostic interaction, Extended X-ray absorption fine structure, 010405 organic chemistry, Chemistry, Ligand, Stereochemistry, Carbon-13, Alkane metathesis, [CHIM.CATA]Chemical Sciences/Catalysis, General Chemistry, Nuclear magnetic resonance spectroscopy, 010402 general chemistry, Metathesis, J-coupling, 01 natural sciences, Biochemistry, Catalysis, 3. Good health, 0104 chemical sciences, Crystallography, Colloid and Surface Chemistry, [CHIM.COOR]Chemical Sciences/Coordination chemistry, ComputingMilieux_MISCELLANEOUS
Abstract: The reaction of [Ta({double_bond}CHtBu)(CH{sub 2}tBu){sub 3}] or [Cp*Ta(CH{sub 3}){sub 4}] with a silica partially dehydroxylated at 700 C gives the corresponding monosiloxy surface complexes [({triple_bond}SiO)Ta({double_bond}CHtBu)(CH{sub 2}tBu){sub 2}] and [({triple_bond}SiO)Ta(CH{sub 3}){sub 3}Cp*] by eliminating a {sigma}-bonded ligand as the corresponding alkane (H-CH{sub 2}tBu or H-CH{sub 3}). EXAFS data show that an adjacent siloxane bridge of the surface plays the role of an extra surface ligand, which most likely stabilizes these complexes as in [({triple_bond}SiO)Ta({double_bond}CHtBu)(CH{sub 2}tBu){sub 2}({triple_bond}SiOSi{triple_bond})] (1a') and [({triple_bond}SiO)Ta(CH{sub 3}){sub 3}Cp*({triple_bond}SiOSi{triple_bond})] (2a'). In the case of [({triple_bond}SiO)Ta({double_bond}CHtBu)(CH{sub 2}tBu){sub 2}({triple_bond}SiOSi{triple_bond})], the structure is further stabilized by an additional interaction: a C-H agostic bond as evidenced by the small J coupling constant for the carbenic C-H (H{sub C-H} = 80 Hz), which was measured by J-resolved 2D solid-state NMR spectroscopy. The product selectivity in propane metathesis in the presence of [({triple_bond}SiO)Ta({double_bond}CHtBu)-(CH{sub 2}tBu){sub 2}({triple_bond}SiOSi{triple_bond})] (1a') as a catalyst precursor and the inactivity of the surface complex [({triple_bond}SiO)Ta-(CH{sub 3}){sub 3}Cp*({triple_bond}SiOSi{triple_bond})] (2a') show that the active site is required to be highly electrophilic and probably involves a metallacyclobutane intermediate.
Published: 2004
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111. La famille aux prises avec les images

Author: Anne Lesage
Subjects: Health (social science), Sociology and Political Science, Social Psychology
Published: 2004
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112. Non-aqueous solvents for DNP surface enhanced NMR spectroscopy

Author: Lyndon Emsley, David Gajan, Melanie Rosay, Aaron J. Rossini, Moreno Lelli, Olivier Ouari, Alexandre Zagdoun, Adrien Bourdolle, Christophe Copéret, Anne Lesage, Werner Maas, Paul Tordo, ISA - Centre de RMN à très hauts champs, Institut des Sciences Analytiques (ISA), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratory for Inorganic, Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Laboratoire de Chimie, Catalyse, Polymères et Procédés, R 5265 (C2P2), Université de Lyon-Université de Lyon-École Supérieure de Chimie Physique Électronique de Lyon (CPE)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Chimie Provence (LCP), Université de Provence - Aix-Marseille 1-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Bruker BioSpin Corporation, ANR EQUIPEX (ANR-10-EQPX-47-01), EU Marie-Curie IIF Fellowship (PIIF-GA-2010-274574), ETH Zurich, European Project, and Université de Lyon-Université de Lyon-École supérieure de Chimie Physique Electronique de Lyon (CPE)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Aqueous solution, 010405 organic chemistry, Chemistry, Metals and Alloys, General Chemistry, Nuclear magnetic resonance spectroscopy, 010402 general chemistry, Photochemistry, 01 natural sciences, Catalysis, Water based, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, Yield (chemistry), Materials Chemistry, Ceramics and Composites, Organic chemistry, DYNAMIC NUCLEAR-POLARIZATION
Abstract: Cover article; International audience; A series of non-aqueous solvents combined with the exogenous biradical bTbK are developed for DNP NMR that yield enhancements comparable to the best available water based systems. 1,1,2,2-tetrachloroethane appears to be one of the most promising organic solvents for DNP solid-state NMR. Here this results in a reduction in experimental times by a factor of 1000. These new solvents are demonstrated with the first DNP surface enhanced NMR characterization of an organometallic complex supported on a hydrophobic surface.
Published: 2012
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113. Solid-State Dynamic Nuclear Polarization at 9.4 and 18.8 T from 100 K to Room Temperature

Author: David Gajan, Moreno Lelli, Aaron J. Rossini, Olivier Ouari, Gilles Casano, Anne Lesage, Lyndon Emsley, Paul Tordo, Sachin Rama Chaudhari, Solid-State NMR Methods for Materials - Méthodes de RMN à l'état solide pour les matériaux, Institut des Sciences Analytiques (ISA), Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie Radicalaire (ICR), Aix Marseille Université (AMU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Ecole Polytechnique Fédérale de Lausanne (EPFL), Financial support is acknowledged from ERC Advanced Grant No. 320860 and EQUIPEX contract ANR-10-EQPX-47-01., ANR-10-EQPX-0047,SENS,RMN de Surface Exalté par Polarisation Dynamique Nucléaire(2010), European Project: 320860,EC:FP7:ERC,ERC-2012-ADG_20120216,HI-SENS(2013), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Catalysis, Chemistry, Surface Chemistry, ENHANCED NMR-SPECTROSCOPY, SPIN-LATTICE-RELAXATION, HIGH-FREQUENCY DNP POLARIZING AGENT, O-TERPHENYL, Cross effect, Communication, Spin–lattice relaxation, Solid-state, Analytical chemistry, General Chemistry, Polarization (waves), Biochemistry, 3. Good health, Solvent, Molecular dynamics, Colloid and Surface Chemistry, Nuclear magnetic resonance, [CHIM]Chemical Sciences, Glass transition
Abstract: We thank Lenaic Leroux for technical help.; International audience; Efficient dynamic nuclear polarization (DNP) in solids, which enables very high sensitivity NMR experiments, is currently limited to temperatures of around 100 K and below. Here we show how by choosing an adequate solvent, 1H cross effect DNP enhancements of over 80 can be obtained at 240 K. To achieve this we use the biradical TEKPol dissolved in a glassy phase of ortho-terphenyl (OTP). We study the solvent DNP enhancement of both TEKPol and BDPA in OTP in the range from 100 to 300 K at 9.4 and 18.8 T. Surprisingly, we find that the DNP enhancement decreases only relatively slowly for temperatures below the glass transition of OTP (Tg = 243 K), and 1H enhancements around 15–20 at ambient temperature can be observed. We use this to monitor molecular dynamic transitions in the pharmaceutically relevant solids Ambroxol and Ibuprofen.
Published: 2015
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114. Tailored Polarizing Hybrid Solids with Nitroxide Radicals Localized in Mesostructured Silica Walls

Author: Pierrick Berruyer, Ta-Chung Ong, Laurent Veyre, Geoffrey Bodenhausen, Henri A. van Kalkeren, Sami Jannin, Lyndon Emsley, Christophe Copéret, Maxim Yulikov, David Baudouin, Basile Vuichoud, Anne Lesage, Mathieu Baudin, Matthieu Cavaillès, Chloé Thieuleux, Daniel L. Silverio, David Gajan, Gunnar Jeschke, Aurélien Bornet, Sachin Rama Chaudhari, Department of Chemistry and Applied Biosciences [ETH Zürich], Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Institut des Sciences et Ingénierie Chimiques (ISIC), Ecole Polytechnique Fédérale de Lausanne (EPFL), Laboratory of Inorganic Chemistry, Laboratoire de Chimie, Catalyse, Polymères et Procédés, R 5265 (C2P2), Centre National de la Recherche Scientifique (CNRS)-École supérieure de Chimie Physique Electronique de Lyon (CPE)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC), Solid-State NMR Methods for Materials - Méthodes de RMN à l'état solide pour les matériaux, Institut des Sciences Analytiques (ISA), Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), ISA - Centre de RMN à très hauts champs, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), ISA - Hyperpolarized Magnetic Resonance, Institut des sciences et d'ingénierie chimiques (ISIC), Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL)-Batochime, Ecole Polytech Fed Lausanne, Inst Sci & Ingn Chim, BCH, CH-1015 Lausanne, Switzerland, Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École supérieure de Chimie Physique Electronique de Lyon (CPE)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université de Lyon-Université de Lyon-École Supérieure de Chimie Physique Électronique de Lyon (CPE)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Nitroxide mediated radical polymerization, Radical, Magic angle spinning dynamic nuclear polarization, Inorganic chemistry, Hybrid organic-inorganic materials, Chemical interaction, 010402 general chemistry, Photochemistry, 01 natural sciences, Biochemistry, Catalysis, Inorganic Chemistry, Paramagnetism, Molecular glasses, Drug Discovery, [CHIM]Chemical Sciences, Molecule, Physics::Chemical Physics, Physical and Theoretical Chemistry, [CHIM.ORGA]Chemical Sciences/Organic chemistry, 010405 organic chemistry, Chemistry, Organic Chemistry, Dissolution dynamic nuclear polarization, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Microwave irradiation, Mesostructured silica
Abstract: International audience; Hyperpolarization by dynamic nuclear polarization relies on the microwave irradiation of paramagnetic radicals dispersed in molecular glasses to enhance the nuclear magnetic resonance (NMR) signals of target molecules. However, magnetic or chemical interactions between the radicals and the target molecules can lead to attenuation of the NMR signal through paramagnetic quenching and/or radical decomposition. Here we describe polarizing materials incorporating nitroxide radicals within the walls of the solids to minimize interactions between the radicals and the solute. These materials can hyperpolarize pure pyruvic acid, a particularly important substrate of clinical interest, while nitroxide radicals cannot be used, even when incorporated in the pores of silica, because of reactions between pyruvic acid and the radicals. The properties of these materials can be engineered by tuning the composition of the wall by introducing organic functionalities.
Published: 2017
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115. Hybrid polarizing solids for pure hyperpolarized liquids through dissolution dynamic nuclear polarization

Author: David Gajan, Henri A. van Kalkeren, Laurent Veyre, Matthew P. Conley, Roberto Melzi, Lyndon Emsley, Wolfram R. Grüning, Aurélien Bornet, Jonas Milani, Martin Schwarzwälder, Basile Vuichoud, Chloé Thieuleux, Sami Jannin, Christophe Copéret, Anne Lesage, Geoffrey Bodenhausen, Solid-State NMR Methods for Materials - Méthodes de RMN à l'état solide pour les matériaux, Institut des Sciences Analytiques (ISA), Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Chimie, Catalyse, Polymères et Procédés, R 5265 (C2P2), Centre National de la Recherche Scientifique (CNRS)-École supérieure de Chimie Physique Electronique de Lyon (CPE)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC), Laboratory of Inorganic Chemistry, Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Université Pierre et Marie Curie - Paris 6 (UPMC), Institut des sciences et d'ingénierie chimiques (ISIC), Ecole Polytechnique Fédérale de Lausanne (EPFL), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Université de Lyon-Université de Lyon-École Supérieure de Chimie Physique Électronique de Lyon (CPE)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Proton Magnetic Resonance Spectroscopy, Analytical chemistry, Acetates, 010402 general chemistry, 01 natural sciences, law.invention, Paramagnetism, Fumarates, law, D-DNP, NMR signal enhancement, Molecule, Hyperpolarization (physics), Carbon-13 Magnetic Resonance Spectroscopy, Pyruvates, Spectroscopy, Dissolution, Incipient wetness impregnation, Multidisciplinary, 010405 organic chemistry, Chemistry, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Temperature, Dipeptides, Nuclear magnetic resonance spectroscopy, Polarizer, molecular imaging, Magnetic Resonance Imaging, mesostructured hybrid silica, 0104 chemical sciences, Solubility, 13. Climate action, Physical Sciences, porous materials
Abstract: International audience; : Hyperpolarization of substrates for magnetic resonance spectroscopy (MRS) and imaging (MRI) by dissolution dynamic nuclear polarization (D-DNP) usually involves saturating the ESR transitions of polarizing agents (PAs; e.g., persistent radicals embedded in frozen glassy matrices). This approach has shown enormous potential to achieve greatly enhanced nuclear spin polarization, but the presence of PAs and/or glassing agents in the sample after dissolution can raise concerns for in vivo MRI applications, such as perturbing molecular interactions, and may induce the erosion of hyperpolarization in spectroscopy and MRI. We show that D-DNP can be performed efficiently with hybrid polarizing solids (HYPSOs) with 2,2,6,6-tetramethyl-piperidine-1-oxyl radicals incorporated in a mesostructured silica material and homogeneously distributed along its pore channels. The powder is wetted with a solution containing molecules of interest (for example, metabolites for MRS or MRI) to fill the pore channels (incipient wetness impregnation), and DNP is performed at low temperatures in a very efficient manner. This approach allows high polarization without the need for glass-forming agents and is applicable to a broad range of substrates, including peptides and metabolites. During dissolution, HYPSO is physically retained by simple filtration in the cryostat of the DNP polarizer, and a pure hyperpolarized solution is collected within a few seconds. The resulting solution contains the pure substrate, is free from any paramagnetic or other pollutants, and is ready for in vivo infusion.
Published: 2014
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116. NMR signatures of the active sites in Sn-beta zeolite

Author: Francisco Núñez-Zarur, Lyndon Emsley, Bernard Malaman, Ive Hermans, Maxence Valla, Aleix Comas-Vives, Patrick Wolf, Christophe Copéret, Anne Lesage, Aaron J. Rossini, Department of Chemistry and Applied Biosciences [ETH Zürich], Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Dept Chem, University of Wisconsin-Madison, Dept Biol & Chem, Solid-State NMR Methods for Materials - Méthodes de RMN à l'état solide pour les matériaux, Institut des Sciences Analytiques (ISA), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut Jean Lamour (IJL), Institut de Chimie du CNRS (INC)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), We acknowledge SNF Grants No. 200021_143600 and 200021_146661, Ambizione project PZ00P2_148059, EQUIPEX contract ANR-10-EQPX-47-01, and ERC Advanced Grant No. 320860 for funding., ANR-10-EQPX-0047,SENS,RMN de Surface Exalté par Polarisation Dynamique Nucléaire(2010), European Project, Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)
Subjects: Magic angle, BAEYER-VILLIGER OXIDATIONS, Inorganic chemistry, Mossbauer spectroscopy, AROMATIC-ALDEHYDES, chemistry.chemical_element, zeolites, [CHIM.INOR]Chemical Sciences/Inorganic chemistry, 010402 general chemistry, WATER-TOLERANT, 01 natural sciences, Catalysis, DENSITY-FUNCTIONAL THEORY, MAGIC-ANGLE, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, active sites, Mössbauer spectroscopy, LEWIS-ACID CATALYST, Zeolite, Polarization (electrochemistry), solid-state NMR spectroscopy, 010405 organic chemistry, General Chemistry, GLUCOSE ISOMERIZATION, DNP SENS, 0104 chemical sciences, Lewis acid catalysis, Crystallography, MEERWEIN-PONNDORF-VERLEY, chemistry, Octahedron, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Density functional theory, DYNAMIC NUCLEAR-POLARIZATION, LACTIC-ACID: active sites, Tin
Abstract: International audience; Dynamic nuclear polarization surface enhanced NMR (DNP-SENS), Mossbauer spectroscopy, and computational chemistry were combined to obtain structural information on the active-site speciation in Sn-beta zeolite. This approach unambiguously shows the presence of framework Sn-IV-active sites in an octahedral environment, which probably correspond to so-called open and closed sites, respectively (namely, tin bound to three or four siloxy groups of the zeolite framework).
Published: 2014
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117. Insights into the Structure and Dynamics of Measles Virus Nucleocapsids by (1)H-detected Solid-state NMR

Author: Anne Lesage, Martin Blackledge, Emeline Barbet-Massin, Lyndon Emsley, Stefan Jehle, Michele Felletti, Rob W.H. Ruigrok, Malene Ringkjøbing Jensen, Robert Schneider, Nicolas Martinez, Guillaume Communie, Guido Pintacuda, Biological Solid-State NMR Methods - Méthodes de RMN à l'état solide en biologie, Institut des Sciences Analytiques (ISA), Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Institut de biologie structurale (IBS - UMR 5075 ), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de virologie moléculaire et structurale (LVMS), Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Institut Laue-Langevin (ILL), ILL, Unit for Virus Host-Cell Interactions [Grenoble] (UVHCI), Centre National de la Recherche Scientifique (CNRS)-European Molecular Biology Laboratory [Grenoble] (EMBL)-Université Joseph Fourier - Grenoble 1 (UJF), Solid-State NMR Methods for Materials - Méthodes de RMN à l'état solide pour les matériaux, Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and Université Joseph Fourier - Grenoble 1 (UJF)-European Molecular Biology Laboratory [Grenoble] (EMBL)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Models, Molecular, Proton Magnetic Resonance Spectroscopy, Biophysics, 010402 general chemistry, 01 natural sciences, Measles virus, 03 medical and health sciences, Nuclear magnetic resonance, Microscopy, Electron, Transmission, AMYLOID FIBRILS, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, Microscopy, BINDING, Escherichia coli, Nucleocapsid, 030304 developmental biology, 0303 health sciences, C-TERMINAL DOMAIN, SPECTROSCOPY, biology, Chemistry, MEMBRANE-PROTEINS, Dynamics (mechanics), Resolution (electron density), CAPSID PROTEIN ASSEMBLIES, biology.organism_classification, 0104 chemical sciences, Nucleoprotein, ANGLE-SPINNING NMR, Solid-state nuclear magnetic resonance, Capsid, Membrane protein, RESOLUTION, RNA, Proteins and Nucleic Acids, NUCLEOPROTEIN
Abstract: International audience; (1)H-detected solid-state nuclear magnetic resonance (NMR) experiments are recorded on both intact and trypsin-cleaved sedimented measles virus (MeV) nucleocapsids under ultra-fast magic-angle spinning. High-resolution (1)H,(15)N-fingerprints allow probing the degree of molecular order and flexibility of individual capsid proteins, providing an exciting atomic-scale complement to electro microscopy (EM) studies of the same systems.
Published: 2014
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118. Silica-surface reorganization during organotin grafting evidenced by ¹¹⁹Sn DNP SENS: a tandem reaction of gem-silanols and strained siloxane bridges

Author: Matthew P, Conley, Aaron J, Rossini, Aleix, Comas-Vives, Maxence, Valla, Gilles, Casano, Olivier, Ouari, Paul, Tordo, Anne, Lesage, Lyndon, Emsley, and Christophe, Copéret
Abstract: Grafting reactive molecular complexes on dehydroxylated amorphous silica is a strategy to develop "single-site" heterogeneous catalysts. In general, only the reactivity of isolated silanols is invoked for silica dehydroxylated at 700 °C ([SiO(2-700)]), though ca. 10% of the surface silanols are in fact geminal Q2-silanols. Here we report the reaction of allyltributylstannane with [SiO(2-700)] and find that the geminal Q2-silanols react to form products that would formally arise from vicinal Q3-silanols that are not present on [SiO(2-700)], indicating that a surface rearrangement occurs. The reorganization of the silica surface is unique to silica dehydroxylated at 700 °C or above. The findings were identified using Dynamic Nuclear Polarization Surface Enhanced NMR Spectroscopy (DNP SENS) combined with DFT calculations.
Published: 2014

119. Unraveling the core-shell structure of ligand-capped Sn/SnOx nanoparticles by surface-enhanced nuclear magnetic resonance, Mössbauer, and X-ray absorption spectroscopies

Author: Maksym V. Kovalenko, Maxence Valla, Dominik Kriegner, Kostiantyn V. Kravchyk, Anne Lesage, Lyndon Emsley, Christophe Copéret, Bernard Malaman, Maarten Nachtegaal, Antoine de Kergommeaux, Peter Reiss, Julian Stangl, Marc Walter, Aaron J. Rossini, Loredana Protesescu, Department of Chemistry and Applied Biosciences [ETH Zürich], Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Swiss Federal Laboratories for Materials Science and Technology [Dübendorf] (EMPA), Solid-State NMR Methods for Materials - Méthodes de RMN à l'état solide pour les matériaux, Institut des Sciences Analytiques (ISA), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institute of Semiconductor and Solid State Physics, Johannes Kepler Universität Linz (JKU), Structures et propriétés d'architectures moléculaire (SPRAM - UMR 5819), Institut Nanosciences et Cryogénie (INAC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Paul Scherrer Institute (PSI), Institut Jean Lamour (IJL), Institut de Chimie du CNRS (INC)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), EQUIPEX contract ANR-10-EQPX-47-01, ERC Advanced Grant No. 320860, ERC Starting Grant No. 306733, EU Marie-Curie IIF fellowship (PIIF-GA-2010-274574), SNF fellowship (200021_143600), Austrian Academy of Sciences (DOC fellowship)., ANR-10-EQPX-0047,SENS,RMN de Surface Exalté par Polarisation Dynamique Nucléaire(2010), AII - Amsterdam institute for Infection and Immunity, APH - Amsterdam Public Health, Global Health, Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut Nanosciences et Cryogénie (INAC), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])
Subjects: Materials science, POLARIZATION, XAS, Analytical chemistry, General Physics and Astronomy, chemistry.chemical_element, Nanoparticle, Li-ion batteries, 02 engineering and technology, [CHIM.INOR]Chemical Sciences/Inorganic chemistry, 010402 general chemistry, OXIDATION, 01 natural sciences, Nanomaterials, dynamic nuclear polarization, Nuclear magnetic resonance, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, General Materials Science, SEMICONDUCTOR NANOCRYSTALS, SNO2, X-ray absorption spectroscopy, HIGH-FREQUENCY, Extended X-ray absorption fine structure, colloidal, General Engineering, Nuclear magnetic resonance spectroscopy, 021001 nanoscience & nanotechnology, TRANSFORMATION, 0104 chemical sciences, EXAFS, Solid-state nuclear magnetic resonance, chemistry, TIN, NMR-SPECTROSCOPY, core/shell structure, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], solid-state NMR, MONODISPERSE, nanoparticles, Absorption (chemistry), 0210 nano-technology, Tin, Dynamic nuclear polarization, Solid-state NMR, Nanoparticles, Colloidal, Core/shell structure
Abstract: A particularly difficult challenge in the chemistry of nanomaterials is the detailed structural and chemical analysis of multicomponent nano-objects. This is especially true for the determination of spatially resolved information. In this study, we demonstrate that dynamic nuclear polarization surface-enhanced solid-state NMR spectroscopy (DNP-SENS), which provides selective and enhanced NMR signal collection from the (near) surface regions of a sample, can be used to resolve the core–shell structure of a nanoparticle. Li-ion anode materials, monodisperse 10–20 nm large tin nanoparticles covered with a ∼3 nm thick layer of native oxides, were used in this case study. DNP-SENS selectively enhanced the weak 119Sn NMR signal of the amorphous surface SnO2 layer. Mössbauer and X-ray absorption spectroscopies identified a subsurface SnO phase and quantified the atomic fractions of both oxides. Finally, temperature-dependent X-ray diffraction measurements were used to probe the metallic β-Sn core and indicated that even after 8 months of storage at 255 K there are no signs of conversion of the metallic β-Sn core into a brittle semiconducting α-phase, a phase transition which normally occurs in bulk tin at 286 K (13 °C). Taken together, these results indicate that Sn/SnOx nanoparticles have core/shell1/shell2 structure of Sn/SnO/SnO2 phases. The study suggests that DNP-SENS experiments can be carried on many types of uniform colloidal nanomaterials containing NMR-active nuclei, in the presence of either hydrophilic (ion-capped surfaces) or hydrophobic (capping ligands with long hydrocarbon chains) surface functionalities., ACS Nano, 8 (3), ISSN:1936-0851, ISSN:1936-086X
Published: 2014
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120. Unraveling the Core\u2013Shell Structure of Ligand-Capped Sn/SnO

Author: Loredana Protesescu, Aaron J. Rossini, Dominik Kriegner, Maxence Valla, Antoine de Kergommeaux, Marc Walter, Kostiantyn V. Kravchyk, Maarten Nachtegaal, Julian Stangl, Bernard Malaman, Peter Reiss, Anne Lesage, Lyndon Emsley, Christophe Copxe9ret, and Maksym V. Kovalenko
Published: 2014

121. Dynamic Nuclear Polarization Enhanced NMR Spectroscopy for Pharmaceutical Formulations

Author: Lyndon Emsley, Alexandre Zagdoun, Moreno Lelli, Martin Schwarzwälder, Cory M. Widdifield, Christophe Copéret, Anne Lesage, and Aaron J. Rossini
Subjects: Active ingredient, Magnetic Resonance Spectroscopy, Molecular Structure, 010405 organic chemistry, Chemistry, Chemistry, Pharmaceutical, Dynamic nuclear polarisation, Analytical chemistry, General Chemistry, Nuclear magnetic resonance spectroscopy, 010402 general chemistry, 01 natural sciences, Biochemistry, Catalysis, Cetirizine dihydrochloride, 0104 chemical sciences, NMR spectra database, Colloid and Surface Chemistry, Rapid acquisition, Polarization (electrochemistry), Nuclear chemistry
Abstract: Dynamic nuclear polarization (DNP) enhanced solid-state NMR spectroscopy at 9.4 T is demonstrated for the detailed atomic-level characterization of commercial pharmaceutical formulations. To enable DNP experiments without major modifications of the formulations, the gently ground tablets are impregnated with solutions of biradical polarizing agents. The organic liquid used for impregnation (here 1,1,2,2-tetrachloroethane) is chosen so that the active pharmaceutical ingredient (API) is minimally perturbed. DNP enhancements (ε) of between 40 and 90 at 105 K were obtained for the microparticulate API within four different commercial formulations of the over-the-counter antihistamine drug cetirizine dihydrochloride. The different formulations contain between 4.8 and 8.7 wt % API. DNP enables the rapid acquisition with natural isotopic abundances of one- and two-dimensional 13C and 15N solid-state NMR spectra of the formulations while preserving the microstructure of the API particles. Here this allowed immediate identification of the amorphous form of the API in the tablet. API–excipient interactions were observed in high-sensitivity 1H–15N correlation spectra, revealing direct contacts between povidone and the API. The API domain sizes within the formulations were determined by measuring the variation of ε as a function of the polarization time and numerically modeling nuclear spin diffusion. Here we measure an API particle radius of 0.3 μm with a single particle model, while modeling with a Weibull distribution of particle sizes suggests most particles possess radii of around 0.07 μm., Journal of the American Chemical Society, 136 (6), ISSN:0002-7863, ISSN:1520-5126
Published: 2014

122. Unraveling the Core-Shell Structure of Ligand-Capped Sn/SnOx Nanoparticles by Surface-Enhanced Nuclear Magnetic Resonance, M\xf6ssbauer, and X-Ray Absorption Spectroscopies

Author: Loredana Protesescu, Aaron J. Rossini, Dominik Kriegner, Maxence Valla, Antoine de Kergommeaux, Marc Walter, Kostiantyn V. Kravchyk, Maarten Nachtegaal, Julian Stangl, Bernard Malaman, Peter Reiss, Anne Lesage, Lyndon Emsley, Christophe Copxe9ret, and Maksym V. Kovalenko
Published: 2014

123. Improved Resolution in Proton NMR Spectroscopy of Powdered Solids

Author: Anne Lesage, Lyndon Emsley, Luminita Duma, and Dimitris Sakellariou
Subjects: Alanine, Dipeptide, Proton, Chemistry, Analytical chemistry, Transverse magnetization, Dipeptides, General Chemistry, Decoupling (cosmology), Solid material, Sensitivity and Specificity, Biochemistry, Line width, Catalysis, Proton nmr spectroscopy, Magnetics, chemistry.chemical_compound, Colloid and Surface Chemistry, Powders, Protons, Nuclear Experiment, Nuclear Magnetic Resonance, Biomolecular
Abstract: We present a new solid-state nuclear magnetic resonance experiment that yields, under CRAMPS decoupling conditions, a significant reduction in proton line widths for powdered organic solids. This experiment which relies on a constant-time acquisition of the proton transverse magnetization, removes the contribution of nonrefocusable broadening from the proton line widths. Although this new technique suffers from relatively low sensitivity, we demonstrate in this paper its feasibility on two model samples, L-alanine and the dipeptide Ala-Asp. In both cases a factor of between 2 and 3 in line width reduction is obtained for most of the proton resonances.
Published: 2001
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124. Complete Resonance Assignment of a Natural Abundance Solid Peptide by Through-Bond Heteronuclear Correlation Solid-State NMR

Author: Anne Lesage, Lyndon Emsley, Patrick Charmont, and Stefan Steuernagel
Subjects: Carbon-13 NMR satellite, Chemistry, Analytical chemistry, General Chemistry, Fluorine-19 NMR, Carbon-13 NMR, Biochemistry, Catalysis, NMR spectra database, Colloid and Surface Chemistry, Solid-state nuclear magnetic resonance, Heteronuclear molecule, Computational chemistry, Proton NMR, Phosphorus-31 NMR spectroscopy
Abstract: The assignment of the NMR spectra of natural abundance medium-sized solid-state organic molecules still represents a challenging problem. In this paper, we show that a complete assignment of all the carbon-13, nitrogen-15, and proton NMR lines of a natural abundance solid peptide can be performed by combining various one-bond and multiple-bond correlation techniques for rotating solids. The assignment of the MAS spectra is shown to be unambiguous and relatively straightforward.
Published: 2000
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125. Homonuclear dipolar decoupling in solid-state NMR using continuous phase modulation

Author: Paul Hodgkinson, Lyndon Emsley, Dimitris Sakellariou, and Anne Lesage
Subjects: Dipole, Continuous phase modulation, Solid-state nuclear magnetic resonance, Chemistry, Phase (matter), Analytical chemistry, General Physics and Astronomy, Physical and Theoretical Chemistry, Molecular physics, Decoupling (electronics), Homonuclear molecule
Abstract: We present a theoretical framework for the use of continuously phase modulated radio-frequency pulses for homonuclear decoupling in solid-state NMR. Within this framework, we have derived new families of decoupling sequences using numerical optimization. One of these sequences is tested experimentally on an ordinary organic solid, and its performance is compared with standard multiple-pulse sequences. (C) 2000 Elsevier Science B.V. All rights reserved.
Published: 2000
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126. 129Xe NMR Spectroscopy of Deuterium-Labeled Cryptophane-A Xenon Complexes: Investigation of Host−Guest Complexation Dynamics

Author: Anne Lesage, and Lyndon Emsley, Thierry Brotin, and André Collet
Subjects: Kinetic model, Analytical chemistry, chemistry.chemical_element, General Chemistry, Nuclear magnetic resonance spectroscopy, Biochemistry, Catalysis, Cryptophane, Colloid and Surface Chemistry, Xenon, Deuterium, chemistry, Atom, Bound state, Physical chemistry, Deuterium labeled
Abstract: We have discovered the ability of 129Xe NMR spectroscopy to discriminate between the xenon complexes of cryptophane-A 1 and its deuterated congeners 2−6 in solution. At 238 K, under slow exchange conditions, the upfield shift experienced by the xenon atom upon complexation by 1 (190 ppm) is increased (up to ∼0.6%) when the hosts are deuterated. By using mixtures of deuterated and nondeuterated hosts, such as 1 and 6, the dynamics of a xenon atom can thus be traced between three different sites (one free and two bound states). We have demonstrated that some of the dynamic features of the exchange between these sites can be extracted from 2D-EXSY experiments, using a suitable kinetic model. We conclude that the exchange of a xenon atom between different hosts occurs by travelling through the solution rather than upon collision of two hosts.
Published: 2000
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127. Gold Nanoparticles Supported on Passivated Silica: Access to an Efficient Aerobic Epoxidation Catalyst and the Intrinsic Oxidation Activity of Gold

Author: Jean-Pierre Candy, Pierre Delichere, Lyndon Emsley, Valérie Caps, Jean-Marie Basset, Christophe Copéret, Anne Lesage, David Gajan, Kevin Guillois, Institut de recherches sur la catalyse et l'environnement de Lyon (IRCELYON), Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)
Subjects: 010405 organic chemistry, Chemistry, Stereochemistry, [CHIM.CATA]Chemical Sciences/Catalysis, General Chemistry, Oxidation Activity, 010402 general chemistry, 01 natural sciences, Biochemistry, Catalysis, 0104 chemical sciences, Improved performance, chemistry.chemical_compound, Colloid and Surface Chemistry, Colloidal gold, Polymer chemistry, Organometallic chemistry
Abstract: Well-defined and perfectly dispersed [( identical withSiO)Au(I)] surface species supported on silica have been obtained via surface organometallic chemistry and transformed upon mild reduction (H(2), 300 degrees C) into small (1.8 +/- 0.6 nm) Au particles supported on silica passivated with SiMe(3) functionalities. Improved performance in liquid-phase aerobic epoxidation has been achieved, and the intrinsic activity of gold in oxidation is revealed.
Published: 2009
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128. Through-Bond Carbon−Carbon Connectivities in Disordered Solids by NMR

Author: Anne Lesage, Lyndon Emsley, and and Michel Bardet
Subjects: chemistry.chemical_classification, Dephasing, Reinforced carbon–carbon, Analytical chemistry, chemistry.chemical_element, General Chemistry, Polymer, Biochemistry, Molecular physics, Catalysis, Homonuclear molecule, chemistry.chemical_compound, Colloid and Surface Chemistry, chemistry, Cellulose, Carbon, Order of magnitude, Line (formation)
Abstract: Using a refocused INADEQUATE NMR experiment we show that homonuclear carbon−carbon through-bond correlations can be obtained in disordered organic solids where the line widths greatly exceed the value of the scalar coupling. The feasibility of the experiment is demonstrated for inhomogeneous samples of 13C-labeled wood and cellulose. The two-dimensional correlation maps are used to assign unambiguously the carbon resonances of this natural polymer. We show that the efficiency of the refocused INADEQUATE experiment depends on the ratio / , where is the apparent relaxation time, deduced from the line width, and is the transverse dephasing time measured in a spin−echo experiment. For cellulose, we find that is larger than by more than 1 order of magnitude and that the experimental efficiency of the refocused INADEQUATE experiment is around 10%, in agreement with calculations. Even in ordinary crystalline organic solids, such as powdered amino acids, large differences are observed between and .
Published: 1999
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129. Assignment and Measurement of Deuterium Quadrupolar Couplings in Liquid Crystals by Deuterium−Carbon NMR Correlation Spectroscopy

Author: Paul Hodgkinson, Stefano Caldarelli, Anne Lesage, Céline Auger, Lyndon Emsley, Institut de recherches sur la catalyse (IRC), Centre National de la Recherche Scientifique (CNRS), and IRCELYON, ProductionsScientifiques
Subjects: 010405 organic chemistry, Chemistry, Analytical chemistry, [CHIM.CATA] Chemical Sciences/Catalysis, [CHIM.CATA]Chemical Sciences/Catalysis, Carbon-13 NMR, 010402 general chemistry, 01 natural sciences, 7. Clean energy, Molecular physics, Thermotropic crystal, Spectral line, 0104 chemical sciences, Surfaces, Coatings and Films, Deuterium, Heteronuclear molecule, Liquid crystal, Materials Chemistry, Physics::Atomic Physics, Physical and Theoretical Chemistry, Spectroscopy, Two-dimensional nuclear magnetic resonance spectroscopy
Abstract: The performance of deuterium-carbon correlation (DECOR) spectroscopy for the assignment and measurement of deuterium quadrupolar couplings in fully deuterated liquid crystalline phases is analyzed. The experiment relies on a broadband polarization transfer step from deuterium to carbons. The efficiency of this step is demonstrated experimentally together with a brief study of cross-polarization dynamics. We show that resolution can be improved by removing the substantial contributions from heteronuclear dipolar couplings in a refocused version of the experiment. Quantification of the quadrupolar couplings is illustrated by the application to the thermotropic liquid crystal 5CB. A complete assignment is obtained by using both short-range and long-range correlations, allowing the individual measurement of all the aromatic couplings that are overlapping in the one-dimensional deuterium spectrum. The heteronuclear C-D couplings are shown to be measurable by direct inspection of the 2D spectra. By way of demonstration, we show that the experiment allows the measurement of quadrupolar couplings as a function of temperature.
Published: 1998
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130. Rapid Proton-Detected NMR Assignment for Proteins with Fast Magic Angle Spinning

Author: Victoria A. Higman, Guido Pintacuda, Loren B. Andreas, I. Akopjana, Andrew J. Pell, Anne Lesage, Monica Stoppini, Lyndon Emsley, Michele Felletti, Martino Bolognesi, Kaspars Tars, Paul Guerry, Hartmut Oschkinat, Emeline Barbet-Massin, Tanguy Le Marchand, Andrea Bertarello, Robert G. Griffin, Matthias Hiller, Vittorio Bellotti, Stefano Ricagno, Torsten Herrmann, Svetlana Kotelovica, James J. Chou, Andrew J. Nieuwkoop, J. Retel, Kristaps Jaudzems, W. Trent Franks, Michael J. Knight, Biological Solid-State NMR Methods - Méthodes de RMN à l'état solide en biologie, Institut des Sciences Analytiques (ISA), Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Leibniz Forschungsinstitut für Molekulare Pharmakolgie = Leibniz Institute for Molecular Pharmacology [Berlin, Allemagne] (FMP), Leibniz Association, MIT, Dept Chem, Massachusetts Institute of Technology (MIT), MIT - Francis Bitter Magnet Lab, Latvian Institute of Organic Synthesis, Biomedical Research & Study Centre, Dept Mol Med, University of Pavia, UCL, Ctr Amyloidosis & Acute Phase Prot, University College of London [London] (UCL)-University ofLondon, Department of Biomolecular Sciences and Biotechnology, University of Milano, School of Medicine, Harvard University [Cambridge], Solid-State NMR Methods for Materials - Méthodes de RMN à l'état solide pour les matériaux, and Agence Nationale de la Recherche (ANR 10-BLAN-713-01), Marie-Curie ITN in the 7th FP of the EC (EAST-NMR no. 228461, BioNMR no. 261863, SMBP no. 211800), CNRS (TGIR-RMN-THC FR3050), Italian Ministry of Research (grant FIRB RBFR109EOS), NIH (grants EB-001960 and EB-002026).
Subjects: Models, Molecular, Proton, 010402 general chemistry, 01 natural sciences, Biochemistry, SEQUENCE, Catalysis, Spectral line, Article, chemistry.chemical_compound, Colloid and Surface Chemistry, Nuclear magnetic resonance, AMYLOID FIBRILS, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, Amide, Magic angle spinning, SPECTRA, Nuclear Magnetic Resonance, Biomolecular, RESONANCE ASSIGNMENT, Carbon Isotopes, Nitrogen Isotopes, 010405 organic chemistry, Chemistry, MEMBRANE-PROTEINS, Resolution (electron density), Resonance, Deuterium Exchange Measurement, Proteins, General Chemistry, CORRELATION SPECTROSCOPY, 0104 chemical sciences, SOLID-STATE NMR, MAS, Solid-state nuclear magnetic resonance, RESOLUTION, ESCHERICHIA-COLI, Protons, Two-dimensional nuclear magnetic resonance spectroscopy, Hydrogen
Abstract: International audience; Using a set of six H-1-detected triple-resonance NMR experiments, we establish a method for sequence-specific backbone resonance assignment of magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectra of 5-30 kDa proteins. The approach relies on perdeuteration, amide H-2/H-1 exchange, high magnetic fields, and high-spinning frequencies (omega(r)/2 pi >= 60 kHz) and yields high-quality NMR data, enabling the use of automated analysis. The method is validated with five examples of proteins in different condensed states, including two microcrystalline proteins, a sedimented virus capsid, and two membrane-embedded systems. In comparison to contemporary C-13/N-15-based methods, this approach facilitates and accelerates the MAS NMR assignment process, shortening the spectral acquisition times and enabling the use of unsupervised state-of-the-art computational data analysis protocols originally developed for solution NMR.
Published: 2014
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131. A well-defined silica-supported tungsten oxo alkylidene is a highly active alkene metathesis catalyst

Author: Lyndon Emsley, Matthew P. Conley, Dmitry V. Peryshkov, Victor Mougel, David Gajan, Richard R. Schrock, William P. Forrest, Christophe Copéret, Anne Lesage, Laboratory of Inorganic Chemistry, Service de Chimie Inorganique et Biologique (SCIB - UMR E3), Institut Nanosciences et Cryogénie (INAC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Centre National de la Recherche Scientifique (CNRS), MIT, Dept Chem, Massachusetts Institute of Technology (MIT), Institut des Sciences Analytiques (ISA), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), ISA - Centre de RMN à très hauts champs, Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), NSF CHE-1111133, ETH fellowship, ETH Zurich-Marie Curie Action for People FEL-08 12-2, Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), and Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL)
Subjects: chemistry.chemical_element, Tungsten, 010402 general chemistry, Metathesis, 01 natural sciences, 7. Clean energy, Biochemistry, Medicinal chemistry, Catalysis, chemistry.chemical_compound, Colloid and Surface Chemistry, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, Organic chemistry, Ethyl oleate, OLEFIN, chemistry.chemical_classification, Olefin fiber, 010405 organic chemistry, Alkene, General Chemistry, Grafting, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, chemistry, COMPLEXES
Abstract: International audience; Grafting (ArO)2W(═O)(═CHtBu) (ArO = 2,6-mesitylphenoxide) on partially dehydroxylated silica forms mostly [(≡SiO)W(═O)(═CHtBu)(OAr)] along with minor amounts of [(≡SiO)W(═O)(CH2tBu)(OAr)2] (20%), both fully characterized by elemental analysis and IR and NMR spectroscopies. The well-defined oxo alkylidene surface complex [(≡SiO)W(═O)(═CHtBu)OAr] is among the most active heterogeneous metathesis catalysts reported to date in the self-metathesis of cis-4-nonene and ethyl oleate, in sharp contrast to the classical heterogeneous catalysts based on WO3/SiO2.
Published: 2013
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132. ChemInform Abstract: In situ Preparation of a Multifunctional Chiral Hybrid Organic-Inorganic Catalyst for Asymmetric Multicomponent Reactions

Author: Anne Lesage, Alexandre Zagdoun, Urbano Díaz, Pilar García-García, Avelino Corma, and Christophe Copéret
Subjects: In situ, biology, Cinchona, Propylamine, General Medicine, biology.organism_classification, Catalysis, chemistry.chemical_compound, Mesoporous organosilica, chemistry, Organic inorganic, Urea, Organic chemistry, Derivative (chemistry)
Abstract: The utilized catalyst is made of a chiral mesoporous organosilica material incorporating a urea-based cinchona derivative and propylamine groups, generated by a co-condensation method.
Published: 2013
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133. A Well-Defined Pd Hybrid Material for the Z-Selective Semihydrogenation of Alkynes Characterized at the Molecular Level by DNP SENS

Author: Laurent Veyre, Lyndon Emsley, W. Trent Franks, David Gajan, Aaron J. Rossini, Hartmut Oschkinat, Moreno Lelli, Olivier Ouari, Ruben M. Drost, Alexandre Zagdoun, Gilles Casano, Mathieu Baffert, Chloé Thieuleux, Cornelis J. Elsevier, Paul Tordo, Matthew P. Conley, Christophe Copéret, Anne Lesage, Laboratory of Inorganic Chemistry, van ‘t Hoff Institute for Molecular Sciences, Universiteit van Amsterdam (UvA), Laboratoire de Chimie, Catalyse, Polymères et Procédés, R 5265 (C2P2), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École Supérieure de Chimie Physique Électronique de Lyon (CPE)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Leibniz Forschungsinstitut für Molekulare Pharmakolgie = Leibniz Institute for Molecular Pharmacology [Berlin, Allemagne] (FMP), Leibniz Association, Institut des Sciences Analytiques (ISA), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), ISA - Centre de RMN à très hauts champs, Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Institut de Chimie Radicalaire (ICR), Aix Marseille Université (AMU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Van't Hoff Institute for Molecular Sciences, Centre National de la Recherche Scientifique (CNRS)-École supérieure de Chimie Physique Electronique de Lyon (CPE)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC), Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), and Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL)
Subjects: FORMIC-ACID, Magnetic Resonance Spectroscopy, Web of science, Formic acid, NHC, Molecular Conformation, chemistry.chemical_element, Alkenes, 010402 general chemistry, 01 natural sciences, Catalysis, chemistry.chemical_compound, Molecular level, NMR spectroscopy, SURFACE ORGANOMETALLIC CHEMISTRY, N-HETEROCYCLIC CARBENE, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, hybrid materials, Organic chemistry, HYDROGENATION CATALYSTS, ENHANCED NMR-SPECTROSCOPY, COMPLEX, HETEROGENEOUS CATALYSTS, 010405 organic chemistry, Chemistry, Organic Chemistry, General Chemistry, Nuclear magnetic resonance spectroscopy, Silicon Dioxide, palladium, ALKENE METATHESIS, 3. Good health, 0104 chemical sciences, carbenes, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Alkynes, semihydrogenation, Hydrogenation, DYNAMIC NUCLEAR-POLARIZATION, Hybrid material, Methane, Palladium
Abstract: International audience; Direct evidence of the conformation of a Pd-N heterocyclic carbene (NHC) moiety imbedded in a hybrid material and of the Pd-NHC bond were obtained by dynamic nuclear polarization surface-enhanced NMR spectroscopy (DNP SENS) at natural abundance in short experimental times (hours). Overall, this silica-based hybrid material containing well-defined Pd-NHC sites in a uniform environment displays high activity and selectivity in the semihydrogenation of alkynes into Z-alkenes.
Published: 2013
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134. Dynamic nuclear polarization surface enhanced NMR spectroscopy

Author: Aaron J. Rossini, Lyndon Emsley, Moreno Lelli, Alexandre Zagdoun, Christophe Copéret, Anne Lesage, ISA - Centre de RMN à très hauts champs, Institut des Sciences Analytiques (ISA), Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Laboratory of Inorganic Chemistry, EQUIPEX contract ANR-10-EQPX-47-01, ETH Zurich, European Union for a Marie Curie fellowship (PIIF-GA-2010-274574)., ANR-10-EQPX-0047,SENS,RMN de Surface Exalté par Polarisation Dynamique Nucléaire(2010), European Project, Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Analytical chemistry, SOLIDS, CATALYSTS, 010402 general chemistry, 01 natural sciences, law.invention, law, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, MAGNETIC-RESONANCE, Porosity, Electron paramagnetic resonance, C-13 NMR, Incipient wetness impregnation, HYBRID MATERIALS, 010405 organic chemistry, Chemistry, General Medicine, General Chemistry, Nuclear magnetic resonance spectroscopy, HYDROGEN, 0104 chemical sciences, ORGANOMETALLIC CHEMISTRY, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Unpaired electron, Spin diffusion, CROSS-POLARIZATION, LIGANDS, Wetting, SENSITIVITY, Mesoporous material
Abstract: International audience; Many of the functions and applications of advanced materials result from their interfacial structures and properties. However, the difficulty in characterizing the surface structure of these materials at an atomic level can often slow their further development Solid-state NMR can probe surface structure and complement established surface science techniques, but its low sensitivity often limits its application. Many materials have low surface areas and/or low concentrations of active/surface sites. Dynamic nuclear polarization (DNP) is one Intriguing method to enhance the sensitivity of solid-state NMR experiments by several orders of magnitude. In a DNP experiment, the large polarization of unpaired electrons is transferred to surrounding nuclei, which provides a maximum theoretical DNP enhancement of similar to 658 for H-1 NMR. In this Account, we discuss the application of DPIP to enhance surface NMR signals, an approach known as DNP surface enhanced NMR spectroscopy (DNP SENS). Enabling DNP for these systems requires bringing an exogeneous radical solution into contact with surfaces without diluting the sample. We proposed the incipient wetness impregnation technique (IWI) a well-known method in materials science, to impregnate porous and particulate materials with just enough radical containing solution to fill the porous volume. IWI offers several advantages: it is extremely simple, provides a uniform wetting of the surface, and does not increase the sample volume or substantially reduce the concentration of the sample. This Account describes the basic principles behind DNP SENS through results obtained for mesoporous and nanoparticulate samples impregnated with radical solutions. We also discuss the quantification of the overall sensitivity enhancements obtained with DNP SENS and compare that with ordinary room temperature NMR spectroscopy. We then review the development of radicals and solvents that give the best possible enhancements today. With the best polarizing mixtures, DNP SENS enhances sensitivity by a factor of up to 100, which decreases acquisition time by five orders of magnitude. Such enhancement enables the detailed and expedient atomic level characterization of the surfaces of complex materials at natural isotopic abundance and opens new avenues for NMR. To illustrate these improvements, we describe the successful application of DNP SENS to characterize hybrid materials, organometallic surface species, and metal-organic frameworks.
Published: 2013
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135. Solid-phase polarization matrixes for dynamic nuclear polarization from homogeneously distributed radicals in mesostructured hybrid silica materials

Author: Gunnar Jeschke, Laurent Veyre, Lyndon Emsley, Christophe Copéret, Anne Lesage, Martin Schwarzwälder, Chloé Thieuleux, Aaron J. Rossini, Olivier Ouari, Wolfram R. Grüning, Matthew P. Conley, David Gajan, Alexandre Zagdoun, Claire Sauvée, Moreno Lelli, Paul Tordo, Maxim Yulikov, ISA - Centre de RMN à très hauts champs, Institut des Sciences Analytiques (ISA), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratory of Inorganic Chemistry, Institut de Chimie Radicalaire (ICR), Aix Marseille Université (AMU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Chimie, Catalyse, Polymères et Procédés, R 5265 (C2P2), Université de Lyon-Université de Lyon-École Supérieure de Chimie Physique Électronique de Lyon (CPE)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-École supérieure de Chimie Physique Electronique de Lyon (CPE)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)
Subjects: Analyte, DYNAMIC nuclear polarisation, Radical, Analytical chemistry, 010402 general chemistry, 01 natural sciences, Biochemistry, Catalysis, NUCLEAR magnetic resonance, Colloid and Surface Chemistry, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, WATER, SILICA, Polarization (electrochemistry), 010405 organic chemistry, Chemistry, Dynamic nuclear polarisation, RADICALS (Chemistry), General Chemistry, PYRUVIC acid, Tetrachloroethane, 0104 chemical sciences, Chemical engineering, Covalent bond, POLARIZATION (Electrochemistry), Mesoporous material, TETRACHLOROETHANE
Abstract: Mesoporous hybrid silica–organic materials containing homogeneously distributed stable mono- or dinitroxide radicals covalently bound to the silica surface were developed as polarization matrixes for solid-state dynamic nuclear polarization (DNP) NMR experiments. For TEMPO-containing materials impregnated with water or 1,1,2,2-tetrachloroethane, enhancement factors of up to 36 were obtained at ∼100 K and 9.4 T without the need for a glass-forming additive. We show that the homogeneous radical distribution and the subtle balance between the concentration of radical in the material and the fraction of radicals at a sufficient inter-radical distance to promote the cross-effect are the main determinants for the DNP enhancements we obtain. The material, as well as an analogue containing the poorly soluble biradical bTUrea, is used as a polarizing matrix for DNP NMR experiments of solutions containing alanine and pyruvic acid. The analyte is separated from the polarization matrix by simple filtration., Journal of the American Chemical Society, 135 (41), ISSN:0002-7863, ISSN:1520-5126
Published: 2013
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136. Out-and-back C-13-C-13 scalar transfers in protein resonance assignment by proton-detected solid-state NMR under ultra-fast MAS

Author: Svetlana Kotelovica, Kaspars Tars, Lyndon Emsley, Inara Akopjana, Andrew J. Pell, Guido Pintacuda, Anne Lesage, W. Trent Franks, Kristaps Jaudzems, J. Retel, Emeline Barbet-Massin, Hartmut Oschkinat, ISA - Centre de RMN à très hauts champs, Institut des Sciences Analytiques (ISA), Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Latvian Institute of Organic Synthesis, Leibniz Forschungsinstitut für Molekulare Pharmakolgie = Leibniz Institute for Molecular Pharmacology [Berlin, Allemagne] (FMP), Leibniz Association, and Biomedical Research & Study Centre
Subjects: DYNAMICS, Proton, Analytical chemistry, 010402 general chemistry, 01 natural sciences, Biochemistry, Solid-state NMR, Through-bond transfers, Viral Proteins, 03 medical and health sciences, Ultra-fast magic-angle spinning, Sensitivity, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, [SDV.BBM.BC]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biochemistry [q-bio.BM], Spectroscopy, Nuclear Magnetic Resonance, Biomolecular, 030304 developmental biology, Fully-protonated and deuterated biosolids, Carbon Isotopes, 0303 health sciences, SPECTROSCOPY, Spins, Chemistry, MEMBRANE-PROTEINS, Chemical shift, Resonance, 0104 chemical sciences, Microcrystalline, ANGLE-SPINNING NMR, Solid-state nuclear magnetic resonance, RESOLUTION, Isotopes of carbon, CROSS-POLARIZATION, PERDEUTERATED PROTEINS, Protons
Abstract: International audience; We present here H-1-detected triple-resonance H/N/C experiments that incorporate CO-CA and CA-CB out-and-back scalar-transfer blocks optimized for robust resonance assignment in biosolids under ultra-fast magic-angle spinning (MAS). The first experiment, (H)(CO)CA(CO)NH, yields H-1-detected inter-residue correlations, in which we record the chemical shifts of the CA spins in the first indirect dimension while during the scalar-transfer delays the coherences are present only on the longer-lived CO spins. The second experiment, (H)(CA)CB(CA)NH, correlates the side-chain CB chemical shifts with the NH of the same residue. These high sensitivity experiments are demonstrated on both fully-protonated and 100 %-H-N back-protonated perdeuterated microcrystalline samples of Acinetobacter phage 205 (AP205) capsids at 60 kHz MAS
Published: 2013
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137. Large molecular weight nitroxide biradicals providing efficient dynamic nuclear polarization at temperatures up to 200 K

Author: Gilles Casano, Alexandre Zagdoun, Lyndon Emsley, Fabien Aussenac, Martin Schwarzwälder, Olivier Ouari, Gunnar Jeschke, Paul Tordo, Christophe Copéret, Maxim Yulikov, Anne Lesage, Aaron J. Rossini, ISA - Centre de RMN à très hauts champs, Institut des Sciences Analytiques (ISA), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie Radicalaire (ICR), Aix Marseille Université (AMU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratory of Inorganic Chemistry, Bruker BioSpin SA, EU Marie-Curie IIF Fellowship (PIIF-GA-2010-274574), SNF for financial support (200021_134775/1), EQUIPEX contract ANR-10-EQPX-47-01, ERC Advanced grant no. 320860, ETH Zurich., European Project, Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)
Subjects: Nitroxide mediated radical polymerization, Magnetic Resonance Spectroscopy, Free Radicals, Proton, PROTEINS, IMPACT, C-13, Analytical chemistry, 010402 general chemistry, 7. Clean energy, 01 natural sciences, Biochemistry, Catalysis, Colloid and Surface Chemistry, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, Phase (matter), Magic angle spinning, Spectroscopy, Polarization (electrochemistry), SURFACE INTERACTIONS, SPECTROSCOPY, Molecular Structure, 010405 organic chemistry, Chemistry, Relaxation (NMR), ELECTRON-SPIN RELAXATION, Temperature, General Chemistry, 0104 chemical sciences, SOLID-STATE NMR, Molecular Weight, Solid-state nuclear magnetic resonance, Nitrogen Oxides, MEMBRANE, GLASSY SOLVENTS
Abstract: A series of seven functionalized nitroxide biradicals (the bTbK biradical and six derivatives) are investigated as exogenous polarization sources for dynamic nuclear polarization (DNP) solid-state NMR at 9.4 T and with ca. 100 K sample temperatures. The impact of electron relaxation times on the DNP enhancement (ε) is examined, and we observe that longer inversion recovery and phase memory relaxation times provide larger ε. All radicals are tested in both bulk 1,1,2,2-tetrachloroethane solutions and in mesoporous materials, and the difference in ε between the two cases is discussed. The impact of the sample temperature and magic angle spinning frequency on ε is investigated for several radicals each characterized by a range of electron relaxation times. In particular, TEKPol, a bulky derivative of bTbK with a molecular weight of 905 g·mol–1, is presented. Its high-saturation factor makes it a very efficient polarizing agent for DNP, yielding unprecedented proton enhancements of over 200 in both bulk and materials samples at 9.4 T and 100 K. TEKPol also yields encouraging enhancements of 33 at 180 K and 12 at 200 K, suggesting that with the continued improvement of radicals large ε may be obtained at higher temperatures., Journal of the American Chemical Society, 135 (34), ISSN:0002-7863, ISSN:1520-5126
Published: 2013
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138. Powder crystallography of pharmaceutical materials by combined crystal structure prediction and solid-state 1H NMR spectroscopy

Author: Robin S. Stein, Elodie Salager, Sirena Bassil, Maria Baias, Jean-Nicolas Dumez, Anne Lesage, Timothy G. Cooper, Graeme M. Day, Hugh P. G. Thompson, Lyndon Emsley, Cory M. Widdifield, ISA - Centre de RMN à très hauts champs, Institut des Sciences Analytiques (ISA), Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Dept Chemistry, University of Cambridge [UK] (CAM), University Southampton, University of Southampton, Agence Nationale de la Recherche (ANR-2010-BLAN-0806-01), Royal Society, and Pfizer Institute for Pharmaceutical Sciences
Subjects: Models, Molecular, HIGH-RESOLUTION H-1, Magnetic Resonance Spectroscopy, C-13, Ab initio, General Physics and Astronomy, ANHYDROUS THEOPHYLLINE, DISTRIBUTED MULTIPOLE, Nuclear magnetic resonance crystallography, Crystal structure, 010402 general chemistry, SHIFT CALCULATIONS, 01 natural sciences, Cocaine, Theophylline, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, 1ST PRINCIPLES, Molecule, Physical and Theoretical Chemistry, Crystallography, QUANTUM-CHEMICAL-CALCULATIONS, PSEUDOPOTENTIALS, 010405 organic chemistry, Chemistry, Chemical shift, 5TH BLIND TEST, Nuclear magnetic resonance spectroscopy, Flutamide, Flufenamic Acid, 0104 chemical sciences, Crystal structure prediction, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, NMR spectra database, NMR-SPECTROSCOPY, Quantum Theory, Powders
Abstract: International audience; A protocol for the ab initio crystal structure determination of powdered solids at natural isotopic abundance by combining solid-state NMR spectroscopy, crystal structure prediction, and DFT chemical shift calculations was evaluated to determine the crystal structures of four small drug molecules: cocaine, flutamide, flufenamic acid, and theophylline. For cocaine, flutamide and flufenamic acid, we find that the assigned H-1 isotropic chemical shifts provide sufficient discrimination to determine the correct structures from a set of predicted structures using the root-mean-square deviation (rmsd) between experimentally determined and calculated chemical shifts. In most cases unassigned shifts could not be used to determine the structures. This method requires no prior knowledge of the crystal structure, and was used to determine the correct crystal structure to within an atomic rmsd of less than 0.12 angstrom with respect to the known reference structure. For theophylline, the NMR spectra are too simple to allow for unambiguous structure selection
Published: 2013
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139. A comparison of the conformational distributions of the achiral symmetric liquid crystal dimer CB7CB in the achiral nematic and chiral twist-bend nematic phases

Author: Geoffrey R. Luckhurst, Anne Lesage, Moreno Lelli, James W. Emsley, School of Chemistry [Southampton, UK], University of Southampton, ISA - Centre de RMN à très hauts champs, Institut des Sciences Analytiques (ISA), Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)
Subjects: Quantitative Biology::Biomolecules, Biaxial nematic, Dimer, 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, 0104 chemical sciences, 3. Good health, Surfaces, Coatings and Films, Condensed Matter::Soft Condensed Matter, chemistry.chemical_compound, Dipole, Crystallography, chemistry, Liquid crystal, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, Phase (matter), Materials Chemistry, Physical and Theoretical Chemistry, Twist, 0210 nano-technology, Chirality (chemistry), Two-dimensional nuclear magnetic resonance spectroscopy
Abstract: International audience; The sets of residual dipolar couplings between carbon and hydrogen nuclei obtained from the proton-encoded 13C 2D NMR experiment are used to investigate the conformational changes which occur when the achiral symmetric liquid crystal dimer CB7CB changes from the achiral nematic to the chiral twist-bend nematic phase. It is found that these changes are a consequence of the chirality of the twist-bend nematic phase, rather than being the driving force for the stability of this phase.
Published: 2013
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140. Evidence for metal-surface interactions and their role in stabilizing well-defined immobilized Ru-NHC alkene metathesis catalysts

Author: Laurent Veyre, Lyndon Emsley, Santosh Kavitake, Johan G. Alauzun, Chloé Thieuleux, Manorja K Samantaray, David Gajan, Moreno Lelli, Christophe Copéret, Anne Lesage, Ahmad Mehdi, Laboratoire de Chimie, Catalyse, Polymères et Procédés, R 5265 (C2P2), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École supérieure de Chimie Physique Electronique de Lyon (CPE)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), department of chemistry, ISA - Centre de RMN à très hauts champs, Institut des Sciences Analytiques (ISA), Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Laboratory of Inorganic Chemistry, the 'Agence Nationale de la Recherche' (ANR-08-BLAN-0151 , EQUIPEX Contract No. ANR-10-EQPX-47-01), and ETH Zurich.
Subjects: Magnetic Resonance Spectroscopy, Surface Properties, 010402 general chemistry, Metathesis, Photochemistry, 01 natural sciences, Biochemistry, Catalysis, chemistry.chemical_compound, Colloid and Surface Chemistry, DESIGN, Catalytic Domain, SILICA, ENHANCED NMR-SPECTROSCOPY, Organometallic chemistry, chemistry.chemical_classification, HYBRID MATERIALS, biology, OLEFIN-METATHESIS, HETEROGENEOUS CATALYSTS, 010405 organic chemistry, Ligand, Alkene, Active site, General Chemistry, Nuclear magnetic resonance spectroscopy, [CHIM.MATE]Chemical Sciences/Material chemistry, Combinatorial chemistry, 0104 chemical sciences, SOLID-STATE NMR, ORGANOMETALLIC CHEMISTRY, chemistry, Metals, biology.protein, Ruthenium Compounds, LIGANDS, DYNAMIC NUCLEAR-POLARIZATION, Phosphine
Abstract: International audience; Secondary interactions are demonstrated to direct the stability of well-defined Ru-NHC-based heterogeneous alkene metathesis catalysts. By providing key stabilization of the active sites, higher catalytic performance is achieved. Specifically, they can be described as interactions between the metal center (active site) and the surface functionality of the support, and they have been detected by surface-enhanced H-1-Si-29 NMR spectroscopy of the ligand and P-31 solid-state NMR of the catalyst precursor. They are present only when the metal center is attached to the surface via a flexible linker (a propyl group), which allows the active site to either react with the substrate or relax, reversibly, to the surface, thus providing stability. In contrast, the use of a rigid linker (here mesitylphenyl) leads to a well-defined active site far away from the surface, stabilized only by a phosphine ligand which under reaction conditions leaves probably irreversibly, leading to faster decomposition and deactivation of the catalysts.
Published: 2013
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141. Trimeric Assembly and Three-Dimensional Structure Model of the FACIT Collagen COL1−NC1 Junction from CD and NMR Analysis

Author: Anne Lesage, Michel van der Rest, and Dominique Marion, François Penin, Christophe Geourjon, and Deleage, Gilbert
Subjects: Models, Molecular, Type XIV collagen, Circular dichroism, Binding Sites, Magnetic Resonance Spectroscopy, Macromolecular Substances, Protein Conformation, Stereochemistry, Chemistry, Circular Dichroism, Molecular Sequence Data, Biochemistry, humanities, FACIT collagen, Crystallography, [SDV.BBM] Life Sciences [q-bio]/Biochemistry, Molecular Biology, Indicators and Reagents, Amino Acid Sequence, Collagen, Disulfides, Structured model, Peptides, Oxidation-Reduction
Abstract: The 3D structure of the COL1-NC1 junction of FACIT type XIV collagen was investigated using GYCDPSSCAG and (GPP*)3GYCDPSSCAG synthetic peptides, circular dichroism, and NMR. At -20 degrees C and under air oxidation catalyzed by Cu2+, the peptide (GPP*)3GYCDPSSCAG is able to self-associated with high yield into a stable triple disulfide bonded trimer. The presence of a triple helical conformation was confirmed by circular dichroism. The analysis of the trimer by 2D NMR provided a set of distance constraints for the noncollagenous part. Molecular models for the 3D structure of COL1-NC1 junction were calculated, using the NMR distance constraints in combination with the 3D structural data recently established by X-ray crystallography [Bella, J., Eaton, M., Brodsky, B., & Berman, H. M. (1994) Science 266, 75-81] for a collagenous triple helix. From the eight theoretically possible arrangements for the three interchain disulfide bonds, only two close disulfide conformers are compatible with the experimental data. The main feature of the trimer structure is the asymmetry of the molecule due to the disulfide bond pattern that induces a particular folding of one chain. This chain forms a turn-like structure locked by two disulfide bonds with the two other chains. The turn-like folding is close to that observed for the cyclized oxidized monomeric peptide. This is the first report of the 3D structure model for a junction between a collagenous triple helical domain and a noncollagenous domain.The 3D structure of the COL1-NC1 junction of FACIT type XIV collagen was investigated using GYCDPSSCAG and (GPP*)3GYCDPSSCAG synthetic peptides, circular dichroism, and NMR. At -20 degrees C and under air oxidation catalyzed by Cu2+, the peptide (GPP*)3GYCDPSSCAG is able to self-associated with high yield into a stable triple disulfide bonded trimer. The presence of a triple helical conformation was confirmed by circular dichroism. The analysis of the trimer by 2D NMR provided a set of distance constraints for the noncollagenous part. Molecular models for the 3D structure of COL1-NC1 junction were calculated, using the NMR distance constraints in combination with the 3D structural data recently established by X-ray crystallography [Bella, J., Eaton, M., Brodsky, B., & Berman, H. M. (1994) Science 266, 75-81] for a collagenous triple helix. From the eight theoretically possible arrangements for the three interchain disulfide bonds, only two close disulfide conformers are compatible with the experimental data. The main feature of the trimer structure is the asymmetry of the molecule due to the disulfide bond pattern that induces a particular folding of one chain. This chain forms a turn-like structure locked by two disulfide bonds with the two other chains. The turn-like folding is close to that observed for the cyclized oxidized monomeric peptide. This is the first report of the 3D structure model for a junction between a collagenous triple helical domain and a noncollagenous domain.
Published: 1996
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142. Thrombopénie après transplantation: La solution était sous le microscope…

Author: Désiré Samba, Laurence Chiche, Chantal Duhamel, Michèle Malet, Renaud Verdon, Anne Lesage, and Ephrem Salamé
Subjects: business.industry, Medicine, business, Analytical Chemistry
Published: 2004
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143. Improved Dynamic Nuclear Polarization Surface-Enhanced NMR Spectroscopy through Controlled Incorporation of Deuterated Functional Groups

Author: Christophe Copéret, Anne Lesage, W. Trent Franks, Martin Schwarzwälder, Wolfram R. Grüning, Lyndon Emsley, Aaron J. Rossini, Alexandre Zagdoun, Matthew P. Conley, Moreno Lelli, Hartmut Oschkinat, ISA - Centre de RMN à très hauts champs, Institut des Sciences Analytiques (ISA), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratory of Inorganic Chemistry, Leibniz Forschungsinstitut für Molekulare Pharmakolgie = Leibniz Institute for Molecular Pharmacology [Berlin, Allemagne] (FMP), Leibniz Association, EU Marie-Curie IFF Fellowship (PIIF-GA-2010-274574), SNF (SNF projeckt 200021_134775/1), EQUIPEX contract ANR-10-EQPX-47-01, ETH Zurich., and European Project
Subjects: Deuterium NMR, Magnetic Resonance Spectroscopy, materials science, Analytical chemistry, Nuclear magnetic resonance crystallography, Fluorine-19 NMR, 010402 general chemistry, 01 natural sciences, Catalysis, dynamic nuclear polarization, NMR spectroscopy, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, Transverse relaxation-optimized spectroscopy, SILICA, ComputingMilieux_MISCELLANEOUS, HYBRID MATERIALS, LOADINGS, 010405 organic chemistry, Chemistry, Silicates, General Medicine, General Chemistry, Nuclear magnetic resonance spectroscopy, Silanes, Carbon-13 NMR, SILYLATION, Deuterium, 0104 chemical sciences, SOLID-STATE NMR, Solid-state nuclear magnetic resonance
Abstract: In a spin: The use of deuterated surface passivation agents is shown to restore dynamic nuclear polarization (DNP) surface-enhanced NMR signals that are reduced in substrates containing methyl groups, while still protecting sensitive sites on the surface (see picture). Furthermore, apolar groups such as [D9]-trimethylsiloxy (TMS) repel radicals (yellow) away from the surface, thus diminishing detrimental paramagnetic effects induced by radical proximity. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Published: 2013
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144. Tetrahydrofuran in TiCl4/THF/MgCl2: a Non-Innocent Ligand for Supported Ziegler-Natta Polymerization Catalysts

Author: Anne Lesage, Vincent Monteil, Sébastien Norsic, Philippe Sautet, Etienne Grau, Christophe Copéret, Laboratory of Inorganic Chemistry, Laboratoire de Chimie, Catalyse, Polymères et Procédés, R 5265 (C2P2), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École supérieure de Chimie Physique Electronique de Lyon (CPE)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Chimie - UMR5182 (LC), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon)-Institut de Chimie du CNRS (INC), ISA - Centre de RMN à très hauts champs, Institut des Sciences Analytiques (ISA), Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), TGE RMN THC Fr3050, Department of Chemistry and Applied Biosciences [ETH Zürich] (D-CHAB), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Université de Lyon-Université de Lyon-École Supérieure de Chimie Physique Électronique de Lyon (CPE)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Michel, Carine
Subjects: surface chemistry, 02 engineering and technology, Natta, 010402 general chemistry, Photochemistry, DFT calculations, 01 natural sciences, Catalysis, chemistry.chemical_compound, 1ST PRINCIPLES, Polymer chemistry, [CHIM]Chemical Sciences, PROPENE POLYMERIZATION, ComputingMilieux_MISCELLANEOUS, Tetrahydrofuran, biology, Chemistry, Ziegler-Natta catalysis, Cationic polymerization, [CHIM.CATA] Chemical Sciences/Catalysis, [CHIM.CATA]Chemical Sciences/Catalysis, General Chemistry, Nuclear magnetic resonance spectroscopy, SS-NMR spectroscopy, MGCL2, [CHIM.MATE]Chemical Sciences/Material chemistry, OLEFIN POLYMERIZATION, 021001 nanoscience & nanotechnology, biology.organism_classification, ethylene polymerization, Non-innocent ligand, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, [CHIM.THEO] Chemical Sciences/Theoretical and/or physical chemistry, [CHIM.POLY]Chemical Sciences/Polymers, Polymerization, HETEROGENEOUS CATALYSIS, DISCOVERY, Alkoxy group, 0210 nano-technology, Ionic polymerization
Abstract: International audience; While Ziegler-Natta (ZN) polymerization is one of the most important catalytic industrial processes, the atomic-scale nature of the catalytically active surface species remains unknown. Coupling high-resolution solid-state NMR spectroscopy with periodic density functional theory (DFT) calculations, we demonstrate that the major surface species in the ZN precatalyst corresponds to an alkoxy Ti(TV) surface species, which probably results from the ring-opening of tetrahydrofuran (THF) on a cationic Ti(IV) species.
Published: 2013
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145. Molecular-level characterization of the structure and the surface chemistry of periodic mesoporous organosilicates using DNP-surface enhanced NMR spectroscopy

Author: Lyndon Emsley, Christophe Copéret, Anne Lesage, Aaron J. Rossini, Wolfram R. Grüning, Alexandre Zagdoun, David Gajan, Department of Chemistry and Applied Biosciences [ETH Zürich], Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), ISA - Centre de RMN à très hauts champs, Institut des Sciences Analytiques (ISA), Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Laboratory of Inorganic Chemistry, EU Marie-Curie IIF Fellowship (PIIF-GA-2010-274574), ETH Zurich, EQUIPEX, European Project, Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Magnetic Resonance Spectroscopy, Surface Properties, Analytical chemistry, General Physics and Astronomy, Natural abundance, 010402 general chemistry, 01 natural sciences, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, Organosilicon Compounds, Physical and Theoretical Chemistry, Particle Size, Polarization (electrochemistry), Molecular Structure, 010405 organic chemistry, Chemistry, Nuclear magnetic resonance spectroscopy, Carbon-13 NMR, FRAMEWORKS, ORGANIC GROUPS, 0104 chemical sciences, 3. Good health, Characterization (materials science), SOLID-STATE NMR, NMR spectra database, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Solid-state nuclear magnetic resonance, WALLS, Physical chemistry, DYNAMIC NUCLEAR-POLARIZATION, Mesoporous material, Porosity
Abstract: International audience; We present the molecular level characterization of a phenylpyridine-based periodicmesoporous organosilicate and its post-functionalized organometallic derivatives through the fast acquisition of high quality natural isotopic abundance 1D C-13, N-15, and Si-29 and 2D 1H-C-13 and 1H-Si-29 solid-state NMR spectra enhanced with dynamic nuclear polarization.
Published: 2013
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146. 13C-detected through-bond correlation experiments for protein resonance assignment by ultra-fast MAS solid-state NMR

Author: Lyndon Emsley, Isabella C. Felli, Anne Lesage, Roberta Pierattelli, Guido Pintacuda, Amy L. Webber, Emeline Barbet-Massin, Michael J. Knight, Andrew J. Pell, ISA - Centre de RMN à très hauts champs, Institut des Sciences Analytiques (ISA), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Dept Chem Ugo Schiff, Università degli Studi di Firenze = University of Florence (UniFI), Magnet Resonance Ctr CERM, Agence Nationale de la Recherche (ANR 08-BLAN-0035-01 et 10-BLAN-713-01), Ente Cassa di Risparmio di Firenze ( Egide 22397RJ et 26000XF), Universita Italo-Francese 26000XF, European Commission, EC (BioNMR) 261863, European Project, Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), and Università degli Studi di Firenze = University of Florence [Firenze] (UNIFI)
Subjects: J-coupling, Time Factors, C-13, Analytical chemistry, 010402 general chemistry, 01 natural sciences, Homonuclear molecule, paramagnetism, MICROCRYSTALLINE PROTEIN, Paramagnetism, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, solid-state nuclear magnetic resonance spectroscopy, magic angle spinning, Magic angle spinning, Peptide bond, Physical and Theoretical Chemistry, Nuclear Magnetic Resonance, Biomolecular, J COUPLING-CONSTANTS, PROTONLESS NMR, Carbon Isotopes, PARAMAGNETIC METALLOPROTEINS, 010405 organic chemistry, Chemistry, Resonance, Proteins, CORRELATION SPECTROSCOPY, superoxide dismutase, Atomic and Molecular Physics, and Optics, 3. Good health, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Crystallography, ANGLE-SPINNING NMR, Solid-state nuclear magnetic resonance, RESOLUTION, CROSS-POLARIZATION, ZINC SUPEROXIDE-DISMUTASE, Two-dimensional nuclear magnetic resonance spectroscopy
Abstract: International audience; We present two sequences which combine ((1)H,(15)N) and ((15)N,(13)C) selective cross-polarization steps with an efficient variant of the J-based homonuclear transfer scheme, in which a spin-state-selective (S(3)E) block is incorporated to improve both resolution and sensitivity in the direct (13)C dimension. We propose these two sequences as a part of a suite of four N-C correlation experiments allowing for the assignment of protein backbone resonances in the solid state. We illustrate these experiments under ultra-fast magic angle spinning conditions on two samples of microcrystalline dimeric human superoxide dismutase (SOD, 153×2 amino acids), in its diamagnetic ("empty", Zn(II)) and paramagnetic (Cu(II), Zn(II)) states.
Published: 2012
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147. The Chirality of a Twist-Bend Nematic Phase Identified by NMR Spectroscopy

Author: Herbert Zimmermann, Bakir A. Timimi, Anne Lesage, Moreno Lelli, Geoffrey R. Luckhurst, James W. Emsley, Laetitia Beguin, ISA - Centre de RMN à très hauts champs, Institut des Sciences Analytiques (ISA), Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Sch Chem, University of Southampton, Max Planck Institute for Medical Research [Heidelberg], and Max-Planck-Gesellschaft
Subjects: Magnetic Resonance Spectroscopy, Stereochemistry, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, Heptanes, chemistry.chemical_compound, Liquid crystal, Phase (matter), Materials Chemistry, Molecule, Physical and Theoretical Chemistry, Methylene, Local field, Heptane, Biphenyl Compounds, Nuclear magnetic resonance spectroscopy, Deuterium, 021001 nanoscience & nanotechnology, Liquid Crystals, 0104 chemical sciences, 3. Good health, Surfaces, Coatings and Films, Condensed Matter::Soft Condensed Matter, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Crystallography, chemistry, 0210 nano-technology, Chirality (chemistry)
Abstract: International audience; One of the defining characteristics of the twist-bend nematic phase, formed by the methylene linked liquid crystal dimer 1 '',7 ''-bis(4-cyanobipheny1-4'-yl) heptane (CB7CB), is its chirality. This new nematic phase, predicted by Dozov, is of particular interest because although the constituent molecules are achiral the phase itself is chiral. Here, we describe the use of NMR spectroscopy to determine experimentally whether in reality the phase is chiral or not. The basis of this novel procedure is that the equivalence of the protons or deuterons in a prochiral methylene group in a nematic phase with D-infinity h symmetry is lost in a chiral phase because its symmetry is reduced to D-infinity on removal of the mirror plane. Recording proton enhanced local field (PELF) NMR experiments shows that in the standard nematic phase all of the methylene groups in the heptane spacer have equivalent pairs of C-H groups but this equivalence is lost for the six prochiral methylene groups with their enantiotopic protons on passing to the twist-bend nematic. Strikingly, this equivalence is not lost for the central methylene group where the two protons are homotopic. We also show how the phase chirgity can be demonstrated with probe molecules which contain deuteriated prochiral methylene groups, using 4-octyl4'-cyanobiphenyl-d(2), perdeuteroacenaphthene-d(10), and acenaphthene-d(4) as examples. For the standard nematic phase deuterium, NMR shows that the deuterons in these methylene groups are equivalent but, as expected, in the twist-bend nematic phase this equivalence is lost. The deuterium NMR spectra of these probe molecules dissolved in CB7CB have been recorded from the isotropic phase, through the nematic and deep into the supercooled twist-bend nematic.
Published: 2012
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148. Combination of DQ and ZQ Coherences for Sensitive Through-Bond NMR Correlation Experiments in Biosolids under Ultra-Fast MAS

Author: Ivano Bertini, Anne Lesage, Emeline Barbet-Massin, Andrew J. Pell, Lyndon Emsley, Isabella C. Felli, Roberta Pierattelli, Guido Pintacuda, Amy L. Webber, Michael J. Knight, ISA - Centre de RMN à très hauts champs, Institut des Sciences Analytiques (ISA), Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Dept Chem Ugo Schiff, Università degli Studi di Firenze = University of Florence [Firenze] (UNIFI), Magnet Resonance Ctr CERM, Agence Nationale de la Recherche (ANR) 08-BLAN-0035-01 10-BLAN-713-01, Ente Cassa di Risparmio di Firenze, Egide (programmes Galiee) 22397RJ 26000XF : Universita Italo-francese 11/12, and EC 261863
Subjects: PROTEINS, Dephasing, Analytical chemistry, 010402 general chemistry, 01 natural sciences, Molecular physics, Spectral line, Magnetization, NMR spectroscopy, Author Keywords: double and zero quantum coherences, magic angle spinning, through-bond interactions, Magic angle spinning, Humans, Physical and Theoretical Chemistry, Nuclear Magnetic Resonance, Biomolecular, DOUBLE-QUANTUM COHERENCE, ZERO-QUANTUM, Spin-½, J COUPLING-CONSTANTS, PROTONLESS NMR, Carbon Isotopes, Nitrogen Isotopes, 010405 organic chemistry, Chemistry, Superoxide Dismutase, Nuclear magnetic resonance spectroscopy, solid state, CORRELATION SPECTROSCOPY, Atomic and Molecular Physics, and Optics, 0104 chemical sciences, SOLID-STATE NMR, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, ANGLE-SPINNING NMR, Solid-state nuclear magnetic resonance, COMPLETE ASSIGNMENT, Quantum Theory, CROSS-POLARIZATION, Crystallization, double and zero quantum coherences, Two-dimensional nuclear magnetic resonance spectroscopy
Abstract: International audience; A double-zero quantum (DZQ)-refocused INADEQUATE experiment is introduced for J-based NMR correlations under ultra-fast (60 kHz) magic angle spinning (MAS). The experiment records two spectra in the same dataset, a double quantumsingle quantum (DQ-SQ) and zero quantumsingle quantum (ZQ-SQ) spectrum, whereby the corresponding signals appear at different chemical shifts in ?1. Furthermore, the spin-state selective excitation (S3E) J-decoupling block is incorporated in place of the second refocusing echo of the INADEQUATE scheme, providing an additional gain in sensitivity and resolution. The two sub-spectra acquired in this way can be treated separately by a shearing transformation, producing two diagonal-free single quantum (SQ-SQ)-type spectra, which are subsequently recombined to give an additional sensitivity enhancement, thus offering an improvement greater than a factor of two as compared to the original refocused INADEQUATE experiment. The combined DZQ scheme retains transverse magnetization on the initially polarized (I) spin, which typically exhibits a longer transverse dephasing time (T2') than its through-bond neighbour (S). By doing so, less magnetization is lost during the refocusing periods in the sequence to give even further gains in sensitivity for the J correlations. The experiment is demonstrated for the correlation between the carbonyl (CO) and alpha (CA) carbons in a microcrystalline sample of fully protonated, [15N,13C]-labelled CuII,?ZnII superoxide dismutase, and its efficiency is discussed with respect to other J-based schemes.
Published: 2012
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149. Nature and structure of aluminum surface sites grafted on silica from a combination of high-field aluminum-27 solid-state NMR spectroscopy and first-principles calculations

Author: Dominique Massiot, Pierre Florian, Emmanuel Callens, Anne Lesage, Anthony Kermagoret, Christophe Copéret, Françoise Delbecq, Philippe Sautet, Rachel N. Kerber, Xavier Rozanska, Laboratoire de Chimie - UMR5182 (LC), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon)-Institut de Chimie du CNRS (INC), Laboratoire de Chimie, Catalyse, Polymères et Procédés, R 5265 (C2P2), Centre National de la Recherche Scientifique (CNRS)-École supérieure de Chimie Physique Electronique de Lyon (CPE)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC), KAUST Catalysis Center, King Abdullah University of Science and Technology (KAUST), Conditions Extrêmes et Matériaux : Haute Température et Irradiation (CEMHTI), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université d'Orléans (UO), ISA - Centre de RMN à très hauts champs, Institut des Sciences Analytiques (ISA), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), King Abdullah University of Science and Technology (KAUST) UK-00017, TGE RMN THC (Fr3050), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École Supérieure de Chimie Physique Électronique de Lyon (CPE)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Université d'Orléans (UO)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Inorganic chemistry, Methylaluminoxane, ARYLOXIDE COMPOUNDS, 010402 general chemistry, 01 natural sciences, Biochemistry, AUGMENTED-WAVE METHOD, Catalysis, Spectral line, ELECTRONIC-STRUCTURE CALCULATIONS, chemistry.chemical_compound, Colloid and Surface Chemistry, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, Magic angle spinning, OLEFIN POLYMERIZATION CATALYSTS, Spectroscopy, 010405 organic chemistry, Chemical shift, LEWIS-ACIDS, General Chemistry, Nuclear magnetic resonance spectroscopy, Mesoporous silica, ETHYLENE POLYMERIZATION, GENERALIZED GRADIENT APPROXIMATION, 0104 chemical sciences, MESOPOROUS SILICA, chemistry, Solid-state nuclear magnetic resonance, HETEROGENEOUS CATALYSIS, MAS NMR, Physical chemistry
Abstract: International audience; The determination of the nature and structure of surface sites after chemical modification of large surface area oxides such as silica is a key point for many applications and challenging from a spectroscopic point of view. This has been, for instance, a long-standing problem for silica reacted with alkylaluminum compounds, a system typically studied as a model for a supported methylaluminoxane and aluminum cocatalyst. While Al-27 solid-state NMR spectroscopy would be a method of choice, it has been difficult to apply this technique because of large quadrupolar broadenings. Here, from a combined use of the highest stable field NMR instruments (17.6, 20.0, and 23.5 T) and ultrafast magic angle spinning (>60 kHz), high-quality spectra were obtained, allowing isotropic chemical shifts, quadnipolar couplings, and asymmetric parameters to be extracted. Combined with first-principles calculations, these NMR signatures were then assigned to actual structures of surface aluminum sites. For silica (here SBA-15) reacted with triethylaluminum, the surface sites are in fact mainly dinuclear Al species, grafted on the silica surface via either two terminal or two bridging siloxy ligands. Tetrahedral sites, resulting from the incorporation of Al inside the silica matrix, are also seen as minor species. No evidence for putative tri-coordinated Al atoms has been found.
Published: 2012
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150. One hundred fold overall sensitivity enhancements for Silicon-29 NMR spectroscopy of surfaces by dynamic nuclear polarization with CPMG acquisition

Author: Melanie Rosay, Moreno Lelli, Fernando Rascón, David Gajan, Alexandre Zagdoun, Lyndon Emsley, Aaron J. Rossini, Werner E. Maas, Christophe Copéret, Anne Lesage, ISA - Centre de RMN à très hauts champs, Institut des Sciences Analytiques (ISA), Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Laboratory for Inorganic Chemistry, Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Bruker BioSpin Corporation, EU Marie-Curie IIF Fellowship (PIIF-GA-2010-274574), ANR EQUIPEX (ANR-10-EQPX-47-01), ETH Zurich, European Project, Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: AMPLITUDE CROSS-POLARIZATION, Silicon, Analytical chemistry, chemistry.chemical_element, RELAXATION, Chemistry, SOLID-STATE NMR, MAGIC ANGLE-SPINNING NMR, DNP, 010402 general chemistry, 01 natural sciences, Paramagnetism, Nuclear magnetic resonance, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, Sample preparation, Aqueous solution, INTEGER QUADRUPOLAR NUCLEI, 010405 organic chemistry, PULSE SEQUENCE, H-1, Pulse sequence, General Chemistry, Nuclear magnetic resonance spectroscopy, 0104 chemical sciences, NMR spectra database, ANGLE-SPINNING NMR, Solid-state nuclear magnetic resonance, RESOLUTION, MAS NMR, COMPLEXES
Abstract: International audience; Dynamic nuclear polarization (DNP) (29)Si solid-state NMR spectra of a hybrid mesoporous silica material impregnated with aqueous biradical solutions have been acquired with cross-polarization (CP) and cross-polarization Carr-Purcell Meiboom-Gill (CP/CPMG) pulse sequences. The integrated intensities (II) and signal to noise ratios (S/N) of the (29)Si solid-state NMR spectra are monitored in order to measure the DNP enhancement factors (epsilon(Si) (CP)) as well as the overall sensitivity enhancement (Sigma(Si) (CP)) available from the combination of DNP and CPMG acquisition. Here, Sigma(Si) (CP) (epsilon(Si) (CP)) ((sic)(Si)) root kappa, where theta(Si) is a factor which quantifies reduction of the NMR signal by paramagnetic effects (quenching) and kappa is the square root of the ratio of nuclear longitudinal relaxation times of the dry material and material impregnated with radical solution. It is found that Sigma(Si) (CP) is always substantially lower than the measured value of epsilon(Si) CP due to paramagnetic effects which reduce the II of the (29)Si CP solid-state NMR spectra at high biradical concentrations. In this system, it is observed that the sample preparation which provides optimal DNP signal enhancement does not provide optimal overall signal enhancement. Notably, optimal signal enhancements are obtained for CPMG acquisition of the (29)Si solid-state NMR spectra when lower radical concentrations are employed due to slower transverse relaxation rates. To the best of our knowledge this is the first study which seeks to quantify the overall sensitivity enhancements available from DNP solid-state NMR experiments.
Published: 2012
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