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1. MMH-2 as a new approach for the prediction of intermolecular interactions: the crystal packing of acetamideElectronic supplementary information (ESI) available: A brief outline of MMH procedures; results of MMH-1/AM1 for acetamide dimers (Fig. S1–S4); additional results comparing MMH-2/AM1 with MP2 and DFT calculations (Tables S1–S12, Fig. S5–S6). See DOI: 10.1039/b905779j

Author

Edelsys Codorniu-HernándezCurrent address: Department of Chemistry. University of Calgary. 2500 University D, A. Daniel Boese, Carsten Schauerte, Alberto Rolo-Naranjo, Ramón Miranda-Quintana, Luis A. Montero-Cabrera, and Roland Boese

Subjects
*MOLECULE-molecule collisions, *ACETAMIDE, *CRYSTALS, *DIMERS, *STATISTICAL thermodynamics, *HAMILTONIAN graph theory, *CONFIGURATION space, *MOLECULAR association
Abstract

A new approach (MMH-2) was applied and tested for the prediction of intermolecular interactions in the crystal packing of acetamide. In MMH-2, energies of random molecular interaction configurations are computed. It uses molecular association quantities from statistical thermodynamics in order to obtain intermolecular interaction motifs that follow a ranking process. The most important motifs are optimized. Here, the AM1 semiempirical Hamiltonian was applied for the calculation and optimization of each obtained configuration and a comparison to MP2 results is provided. Such a stepwise procedure follows the assumed genesis of crystal growth without using experimental input. For evaluation purposes, graph set analysis was used to classify the structural patterns of both acetamide polymorphs. It was also necessary to introduce a new geometrical similarity index for the comparison of calculated and experimental motifs. As a result, all experimental hydrogen bond patterns were found and molecular synthons in both polymorphic acetamide structures were predicted as local minima. This suggests a new strategy for crystal structure prediction of flexible molecules with a possible subsequent progress in crystal engineering in silico. [ABSTRACT FROM AUTHOR]

Published
2009
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2. Spontaneous Ammonia Activation Through Coordination‐Induced Bond Weakening in Molybdenum Complexes of a Dianionic Pentadentate Ligand Platform

Author

C. Christopher Almquist, Nicole Removski, Thayalan Rajeshkumar, Benjamin S. Gelfand, Laurent Maron, Warren E. Piers, Department of Chemistry, University of Calgary, University of Calgary, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-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), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Molybdenum, Ligand Design, [CHIM]Chemical Sciences, Density Functional Calculations, General Medicine, General Chemistry, Bond Activation, Ammonia Oxidation, Catalysis
Abstract

Ammonia oxidation catalyzed by molecular compounds is of current interest as a carbon-free source of dihydrogen. Activation of N-H bonds through coordination to transition metal centers is a key reaction in this process. We report the substantial activation of ammonia via reaction with low-valent molybdenum complexes of a diborate pentadentate ligand system. Spontaneous loss of dihydrogen from (B

Published
2022
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4. Activation of ammonia and hydrazine by electron rich Fe(<scp>ii</scp>) complexes supported by a dianionic pentadentate ligand platform through a common terminal Fe(<scp>iii</scp>) amido intermediate

Author

Warren E. Piers, Michael L. Neidig, Benjamin S. Gelfand, Peter G. N. Neate, Lucie Nurdin, Yan Yang, Laurent Maron, Jian-Bin Lin, Department of Chemistry, University of Calgary, University of Calgary, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-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), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), University of Rochester [USA], Department of Chemical and Petroleum Engineering [Calgary], Natural Sciences and Engineering Research Council of Canada, French CNRS PICS project, Alberta Innovates Technology Futures, Vanier Canada Graduate Scholarships, Chinese Scholarship Council (CSC), and National Institutes of Health [R01GM111480]

Subjects
Hydrogen, 010405 organic chemistry, Ligand, Dimer, Hydrazine, chemistry.chemical_element, General Chemistry, 010402 general chemistry, 01 natural sciences, Redox, 3. Good health, 0104 chemical sciences, Adduct, Chemistry, Ammonia, chemistry.chemical_compound, chemistry, Transition metal, Polymer chemistry, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph]
Abstract

We report the use of electron rich iron complexes supported by a dianionic diborate pentadentate ligand system, B2Pz4Py, for the coordination and activation of ammonia (NH3) and hydrazine (NH2NH2). For ammonia, coordination to neutral (B2Pz4Py)Fe(ii) or cationic [(B2Pz4Py)Fe(iii)]+ platforms leads to well characterized ammine complexes from which hydrogen atoms or protons can be removed to generate, fleetingly, a proposed (B2Pz4Py)Fe(iii)–NH2 complex (3Ar-NH2). DFT computations suggest a high degree of spin density on the amido ligand, giving it significant aminyl radical character. It rapidly traps the H atom abstracting agent 2,4,6-tri-tert-butylphenoxy radical (ArO˙) to form a C–N bond in a fully characterized product (2Ar), or scavenges hydrogen atoms to return to the ammonia complex (B2Pz4Py)Fe(ii)–NH3 (1Ar-NH3). Interestingly, when (B2Pz4Py)Fe(ii) is reacted with NH2NH2, a hydrazine bridged dimer, (B2Pz4Py)Fe(ii)–NH2NH2–Fe(ii)(B2Pz4Py) ((1Ar)2-NH2NH2), is observed at −78 °C and converts to a fully characterized bridging diazene complex, 4Ar, along with ammonia adduct 1Ar-NH3 as it is allowed to warm to room temperature. Experimental and computational evidence is presented to suggest that (B2Pz4Py)Fe(ii) induces reductive cleavage of the N–N bond in hydrazine to produce the Fe(iii)–NH2 complex 3Ar-NH2, which abstracts H˙ atoms from (1Ar)2-NH2NH2 to generate the observed products. All of these transformations are relevant to proposed steps in the ammonia oxidation reaction, an important process for the use of nitrogen-based fuels enabled by abundant first row transition metals., Synopsis: a highly reactive Fe(iii)–NH2 complex is generated via activation of ammonia or hydrazine in reactions of relevance to fundamental steps in ammonia oxidation processes mediated by an abundant, first row transition metal.

Published
2021
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7. Preface to the special collection in honor of Fernand Spiegelman

Author

Florent Calvo, Dennis R. Salahub, Laboratoire Interdisciplinaire de Physique [Saint Martin d’Hères] (LIPhy ), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), Department of Chemistry, University of Calgary, and University of Calgary

Subjects
Materials science, 010304 chemical physics, Honor, 0103 physical sciences, [CHIM]Chemical Sciences, Art history, Physical and Theoretical Chemistry, 010402 general chemistry, 01 natural sciences, ComputingMilieux_MISCELLANEOUS, 0104 chemical sciences
Abstract

International audience

Published
2021
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9. A monoanionic pentadentate ligand platform for scandium-pnictogen multiple bonds

Author

Warren E. Piers, Laurent Maron, Yan Yang, Evan A. Patrick, Benjamin S. Gelfand, University of Calgary, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-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), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Department of Chemical and Petroleum Engineering [Calgary], Department of Chemistry, University of Calgary, NSERC of Canada, Canada Research Chair, Alberta Innovates, and HPCs CALcul en Midi-Pyrenees (CALMIP-EOS grant) [1415]

Subjects
010405 organic chemistry, Chemistry, Ligand, Metals and Alloys, chemistry.chemical_element, General Chemistry, 010402 general chemistry, 01 natural sciences, Multiple bonds, Catalysis, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, 3. Good health, Crystallography, Phosphinidene, Yield (chemistry), Materials Chemistry, Ceramics and Composites, Scandium, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Pnictogen, Bond cleavage
Abstract

International audience; A new monoanionic pentadentate ligand is designed to accommodate Sc = E bonds (E = N, P). The imido complex is stable enough to isolate and characterize, and reacts rapidly with CO2. The phosphinidene, on the other hand, is highly reactive and induces C-C bond cleavage to yield a phosphido-pyridyl complex which also undergoes rapid reacton with CO2.

Published
2021
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10. Indeno[1,2-b]thiophene End-capped Perylene Diimide: Should the 1,6-Regioisomers be systematically considered as a byproduct?

Author

Pablo Simón Marqués, Francesco Tintori, José María Andrés Castán, Pierre Josse, Clément Dalinot, Magali Allain, Gregory Welch, Philippe Blanchard, Clément Cabanetos, MOLTECH-Anjou, Université d'Angers (UA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Department of Chemistry, University of Calgary, and University of Calgary

Subjects
Energy, Science, lcsh:R, Medicine, Organic chemistry, lcsh:Medicine, [CHIM]Chemical Sciences, Materials chemistry, lcsh:Q, lcsh:Science, Article
Abstract

International audience; Usually considered as a byproduct, the 1,6-dibrominated PDI has rarely been functionalized for the preparation of electro-active conjugated molecules, particularly in the field of organic photovoltaics. In light of the literature, one can ask oneself: Does a 1,7-isomer based functional molecule systematically perform better than its 1,6-analogue? To answer this question, we report herein the synthesis and direct comparison of two indeno[1,2-b]thiophene (IDT) end-capped perylene diimide regioisomers (PDI) (1,6 and 1,7) used as non-fullerene acceptors in organic solar cells. It turned out that in our case, ie, when blended with the well-known PTB7-Th donor polymer, higher performance was reached for devices made with the 1,6-analogue. Major contributors to the recent resurgence of organic photovoltaics (OPVs) 1-3 , molecular non-fullerene accep-tors (NFAs) have driven up power conversion efficiencies (PCEs), in a short amount of time, from "what a fuller-ene derivative does best" 4,5 to more than 15% 6-8. Although these records were reached with indacenodithiophene derivatives, perylene diimides (PDIs) have always held an important place among the electron transporting materials due to their excellent thermal, chemical and photochemical stabilities combined with their singular optical, redox and charge transport properties 9,10. Nonetheless, the PDI extended π-conjugated structure typically suffers from an excessive π-π stacking tendency, forming micrometer-sized crystallites that are detrimental for an efficient charge separation in bulk heterojunction (BHJ) solar cells 11-14. To tackle this problem, important efforts have been devoted to functionalize the peripheral positions, namely the bay (1,6,7,12) and ortho positions (2,5,8,11) 3,9,15-18 , leading to profuse design principles and above all, to a better understanding of the structure-property relationships (Fig. 1) 19-28. The key reaction, the dibromination of the bay positions, holds a special place by providing a precursor to many published molecular and macromolecular π-functional PDI based materials, namely the 1,7-isomer 29. Also generated during the reaction, but in smaller ratio, the 1,6-isomer has not triggered such interest. Conversely, the latter has even motivated the development of purification procedures and methods since usually considered as an impurity 30. As a result, only limited studies aiming at comparing the properties of molecular architectures based on both regioisomers have been reported so far 31-33 , particularly in the field of OPVs. In fact, and to the best of our knowledge , only one paper can be found where the two bromo isomers (1,6 and 1,7) were functionalized either by triphenylamine (TPA) or benzodithiophene (BDT) moieties for the preparation of NFAs 34. In all cases, best PCEs (ca 0.67%) were reached with the 1,7-isomers once blended with different donor polymers and attributed to a better phase separation. Considering the scarcity of reported examples, it would be unthinkable to draw meaningful conclusions on the systematic use of one isomer over the other.

Published
2020
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11. Polyphenols bind to low density lipoprotein at biologically relevant concentrations that are protective for heart disease

Author

Wei-Cheng Tung, Njara Rakotomanomana, Bryan Rizzo, Joe A. Vinson, Yusef Dabbagh, Paul W. Needs, Olivier Dangles, Paul A. Kroon, Mark Romanczyk, Suraj Saraswat, Rocio Rebollido-Rios, Edelsys Codorniu-Hernández, Karen Weikel, University of Scranton, Department of Chemistry, University of Calgary, University of Calgary, University of Duisburg-Essen, University Hospital of Cologne [Cologne], Quadram Institute Bioscience, Sécurité et Qualité des Produits d'Origine Végétale (SQPOV), and Avignon Université (AU)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)

Subjects
0301 basic medicine, Antioxidant, Cardiotonic Agents, binding, Swine, medicine.medical_treatment, Biophysics, Serum albumin, Serum Albumin, Human, heart disease, Biochemistry, Antioxidants, 03 medical and health sciences, chemistry.chemical_compound, Lipid oxidation, lipid oxidation, Extracellular, medicine, Animals, Humans, Lipoprotein oxidation, [SDV.BBM.BC]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biochemistry [q-bio.BM], Molecular Biology, polyphenols, metabolites, 030102 biochemistry & molecular biology, biology, food and beverages, 3. Good health, Lipoproteins, LDL, lipoproteins, 030104 developmental biology, chemistry, Polyphenol, Low-density lipoprotein, biology.protein, Quercetin, Biologie, Oxidation-Reduction, [SDV.AEN]Life Sciences [q-bio]/Food and Nutrition, Protein Binding
Abstract

International audience; There is ample evidence in the epidemiological literature that polyphenols, the major non-vitamin antioxidants in plant foods and beverages, have a beneficial effect on heart disease. Until recently other mechanisms which polyphenols exhibit such as cell signaling and regulating nitric oxide bioavailability have been investigated. The oxidation theory of atherosclerosis implicates LDL oxidation as the beginning step in this process. Nine polyphenols from eight different classes and several of their O-methylether, O-glucuronide and O-sulfate metabolites have been shown in this study to bind to the lipoproteins and protect them from oxidation at lysosomal/inflammatory pH (5.2), and physiological pH (7.4). Polyphenols bind to the apoprotein at pH 7.4 with Kb > 106M- 1 and the number of molecules of polyphenols bound per LDL particle under saturation conditions varied from 0.4 for ferulic acid to 13.1 for quercetin. Competition studies between serum albumin and LDL show that substantial lipoprotein binding occurs even in the presence of a great molar excess of albumin, the major blood protein. These in vitro results are borne out by published human supplementation studies showing that polyphenol metabolites from red wine, olive oil and coffee are found in LDL even after an overnight fast. A single human supplementation with various fruit juices, coffee and tea also produced an ex vivo protection against lipoprotein oxidation under postprandial conditions. This in vivo binding is heart-protective based on published olive oil consumption studies. Relevant to heart disease, we hypothesize that the binding of polyphenols and metabolites to LDL functions as a transport mechanism to carry these antioxidants to the arterial intima, and into endothelial cells and macrophages. Extracellular and intracellular polyphenols and their metabolites are heartprotective by many mechanisms and can also function as potent “intraparticle” and intracellular antioxidants due to their localized concentrations that can reach as high as the micromolar level. Low plasma concentrations makepolyphenols and their metabolites poor plasma antioxidants but their concentration in particles such as lipoproteins and cells is high enough for polyphenols to provide cardiovascular protection by direct antioxidant effects and by other mechanisms such as cell signaling.

Published
2020
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12. The Experimentalist's Guide to the Cycloid, or Noncollinear Antiferromagnetism in Epitaxial BiFeO3

Author

Stuart R. Burns, Daniel Sando, Oliver Paull, Jean Juraszek, Valanoor Nagarajan, Department of Chemistry, University of Calgary, University of Calgary, School of Materials Science and Engineering [Sydney], University of New South Wales [Sydney] (UNSW), Groupe de physique des matériaux (GPM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Matériaux Avancés (IRMA), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), and Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, Condensed matter physics, Magnetism, Mechanical Engineering, 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, Ferroelectricity, 0104 chemical sciences, chemistry.chemical_compound, chemistry, Mechanics of Materials, Cycloid, Electric field, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Antiferromagnetism, General Materials Science, Multiferroics, 0210 nano-technology, ComputingMilieux_MISCELLANEOUS, Spin-½, Bismuth ferrite
Abstract

Bismuth ferrite (BiFeO3 ) is one of the most widely studied multiferroics. The coexistence of ferroelectricity and antiferromagnetism in this compound has driven an intense search for electric-field control of the magnetic order. Such efforts require a complete understanding of the various exchange interactions that underpin the magnetic behavior. An important characteristic of BiFeO3 is its noncollinear magnetic order; namely, a long-period incommensurate spin cycloid. Here, the progress in understanding this fascinating aspect of BiFeO3 is reviewed, with a focus on epitaxial films. The advances made in developing the theory used to capture the complexities of the cycloid are first chronicled, followed by a description of the various experimental techniques employed to probe the magnetic order. To help the reader fully grasp the nuances associated with thin films, a detailed description of the spin cycloid in the bulk is provided. The effects of various perturbations on the cycloid are then described: magnetic and electric fields, doping, epitaxial strain, finite size effects, and temperature. To conclude, an outlook on possible device applications exploiting noncollinear magnetism in BiFeO3 films is presented. It is hoped that this work will act as a comprehensive experimentalist's guide to the spin cycloid in BiFeO3 thin films.

Published
2020
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18. Spectroscopic Engineering toward Near-Infrared Absorption of Materials Containing Perylene Diimide

Author

Jonathan Cann, Gregory C. Welch, Clément Cabanetos, MOLTECH-Anjou, Institut de Chimie du CNRS (INC)-Université d'Angers (UA)-Centre National de la Recherche Scientifique (CNRS), Department of Chemistry, University of Calgary, University of Calgary, and Université d'Angers (UA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, 02 engineering and technology, General Chemistry, Chromophore, Conjugated system, 010402 general chemistry, 021001 nanoscience & nanotechnology, Photochemistry, 01 natural sciences, 0104 chemical sciences, chemistry.chemical_compound, Acetylene, chemistry, Electrochromism, Diimide, [CHIM]Chemical Sciences, Molecule, 0210 nano-technology, Absorption (electromagnetic radiation), Perylene
Abstract

International audience; The ability to tune the dye structure synthetically has been crucial in the development of materials with tailored properties for given applications. In this contribution, a series of discrete molecules are reported, which are constructed from the perylene diimide (PDI) chromophore and three dyes, namely thienyl diketopyrrolopyrrole (DPPTh2), pyridyl diketopyrrolopyrrole (DPPPyr2), and thienoisoindigo (TII). Through the choice of dye molecule and linking of the dye and PDI through conjugated acetylene bridges, the light-harvesting characteristics can be engineered to exhibit optical absorption in the range 300–900 nm. Each molecule shows ambipolar redox behavior, leading to unique electrochromic behavior.

Published
2017
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19. Thienoisoindigo end-capped molecular donors for organic photovoltaics: Effect of the central π-conjugated connector

Author

Clément Cabanetos, Philippe Blanchard, Sylvie Dabos-Seignon, Seth M. McAfee, Pierre Josse, Gregory C. Welch, MOLTECH-Anjou, Institut de Chimie du CNRS (INC)-Université d'Angers (UA)-Centre National de la Recherche Scientifique (CNRS), Department of Chemistry, University of Calgary, University of Calgary, and Université d'Angers (UA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Fullerene derivatives, Materials science, Organic solar cell, Process Chemistry and Technology, General Chemical Engineering, [CHIM.MATE]Chemical Sciences/Material chemistry, 02 engineering and technology, Conjugated system, Fluorene, 010402 general chemistry, 021001 nanoscience & nanotechnology, Photochemistry, Grafting, 01 natural sciences, 7. Clean energy, Polymer solar cell, 0104 chemical sciences, chemistry.chemical_compound, chemistry, [CHIM]Chemical Sciences, Organic chemistry, Molecule, 0210 nano-technology, Molecular materials, ComputingMilieux_MISCELLANEOUS
Abstract

The synthesis, characterization and preliminary evaluation of two thienoisoindigo ( TII ) based molecules as donor materials in air processed bulk heterojunction solar cells are reported herein. The latter were built by grafting TII dyes on two different π-conjugated central cores, namely the cyclopentadithiophene and the fluorene units. Once blended with fullerene derivatives, power conversion efficiencies approaching 3% were measured, ranking amongst the highest reported value for thienoisoindigo-based molecular materials.

Published
2017
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20. Hydrolysis of scandium alkyl derivatives supported by a pentadentate diborate ligand: Interconversion of hydroxo and oxo complexes

Author

Benjamin S. Gelfand, Yan Yang, Warren E. Piers, Jian-Bin Li, Laurent Maron, Daniel W. Beh, Department of Chemistry, University of Calgary, University of Calgary, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-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), 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 sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
chemistry.chemical_classification, 010405 organic chemistry, Ligand, Dimer, chemistry.chemical_element, Protonation, 010402 general chemistry, 01 natural sciences, Decomposition, 0104 chemical sciences, Inorganic Chemistry, Hydrolysis, chemistry.chemical_compound, chemistry, Polymer chemistry, Materials Chemistry, Reactivity (chemistry), Scandium, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Physical and Theoretical Chemistry, Alkyl
Abstract

Uncontrolled reaction of water with scandium alkyls (compounds 1-R) supported by a dianionic, pentadentate ligand leads to rapid formation of an oxo-bridged dimer (2). Solid state samples can be exposed to ambient atmosphere to generate samples enriched in the bridging dihydroxo dimer 3, which slowly converts to the m-oxo species with elimination of water. DFT computations show that 3 is actually more thermodynamically stable than 2, but the reactivity of 3 with the water eliminated leads to its decomposition to 2 and several hydrolysis products. Some of these products were characterized by X-ray crystallography, specifically a hexameric scandium dihydroxo cluster (4) in which the pentadentate ligand has partially demetallated. Attempts to synthesize hydroxo complex 3 by protonation of 2 also lead to hydrolysis products.

Published
2020
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21. triazatruxene-based molecular dyad for single-component organic solar cells

Author

Labrunie, Antoine, Londi, Giacomo, Dayneko, Sergey, Blais, Martin, Dabos-Seignon, Sylvie, Welch, Gregory, Beljonne, David, Blanchard, Philippe, Cabanetos, Clément, MOLTECH-Anjou, Université d'Angers (UA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Department of Chemistry 'Ugo Schiff', Università degli Studi di Firenze = University of Florence [Firenze] (UNIFI), Department of Chemistry, University of Calgary, University of Calgary, Fonds de la Recherche Scientifique [FNRS], and Cabanetos, Clément

Subjects
[CHIM] Chemical Sciences, [CHIM]Chemical Sciences, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2019

22. Ternary organic solar cells: using molecular donor or acceptor third components to increase open circuit voltage

Author

Clément Cabanetos, Jonathan Cann, Sergey V. Dayneko, Arthur D. Hendsbee, Gregory C. Welch, Department of Chemistry, University of Calgary, University of Calgary, MOLTECH-Anjou, Université d'Angers (UA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institute for Computer Graphics and Vision [Graz] (ICG), and Graz University of Technology [Graz] (TU Graz)

Subjects
Fullerene, Organic solar cell, Open-circuit voltage, Chemistry, Energy conversion efficiency, Doping, 02 engineering and technology, General Chemistry, [CHIM.MATE]Chemical Sciences/Material chemistry, 010402 general chemistry, 021001 nanoscience & nanotechnology, 7. Clean energy, 01 natural sciences, Acceptor, Catalysis, 0104 chemical sciences, law.invention, Chemical engineering, law, Solar cell, Materials Chemistry, 0210 nano-technology, Ternary operation, ComputingMilieux_MISCELLANEOUS
Abstract

This report demonstrates that the open circuit voltage (VOC) and power conversion efficiency (PCE) of polymer:fullerene (PBDB-T:PC60BM) organic solar cells can be simultaneously enhanced by introducing a molecular π-conjugated donor or acceptor as a third component, thus affording high performance ternary blend devices. The use of a PDI-based acceptor “tPDI2N-hex” or benzothioxanthene-based donor “tBTI-IDT” as a third component leads to VOC increases of 60 to 150 mV without significant loss in power conversion efficiency (PCE). The best solar cell PCE of 8.8% was achieved by doping the PBDB-T:PC60BM system with 10% by weight of tPDI2N-hex.

Published
2019
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23. New construction of perylenediimide derivatives as original systems for organic solar cells

Author

R. El, Berjawi, F., Tintori, G., Welch, P., Hudhomme, MOLTECH-Anjou, Université d'Angers (UA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Department of Chemistry, University of Calgary, University of Calgary, and HUDHOMME, Piétrick

Subjects
[SPI]Engineering Sciences [physics], [SPI] Engineering Sciences [physics], [CHIM] Chemical Sciences, [CHIM]Chemical Sciences, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2019

24. Functionalization of the Benzothioxanthene block: Toward New pi-Conjugated Systems for Organic Electronic Applications

Author

Dalinot, Clément, Andrés Castán, José María, Josse, Pierre, Risko, Chad, Lessard, Benoit, Gregory, Welch, Blanchard, Philippe, Cabanetos, Clément, MOLTECH-Anjou, Université d'Angers (UA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Department of Chemistry, University of Kentucky, University of Kentucky, University of Ottawa [Ottawa], Department of Chemistry, University of Calgary, University of Calgary, and BLANCHARD, Philippe

Subjects
[CHIM.MATE] Chemical Sciences/Material chemistry, [CHIM.ORGA]Chemical Sciences/Organic chemistry, [CHIM] Chemical Sciences, [CHIM]Chemical Sciences, [CHIM.MATE]Chemical Sciences/Material chemistry, [CHIM.ORGA] Chemical Sciences/Organic chemistry
Abstract

1er Prix poster; National audience

Published
2019

25. Simply Complex: The Efficient Synthesis of an Intricate Molecular Acceptor for High-Performance Air-Processed and Air-Tested Fullerene-Free Organic Solar Cells

Author

Gregory C. Welch, Clément Cabanetos, Seth M. McAfee, Pierre Josse, Philippe Blanchard, Sergey V. Dayneko, Department of Chemistry, University of Calgary, University of Calgary, MOLTECH-Anjou, Université d'Angers (UA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Institut de Chimie du CNRS (INC)-Université d'Angers (UA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
chemistry.chemical_classification, Fullerene, Organic solar cell, General Chemical Engineering, Energy conversion efficiency, 02 engineering and technology, General Chemistry, Polymer, 010402 general chemistry, 021001 nanoscience & nanotechnology, Photochemistry, 01 natural sciences, Small molecule, Acceptor, 0104 chemical sciences, chemistry.chemical_compound, chemistry, Diimide, Materials Chemistry, [CHIM]Chemical Sciences, 0210 nano-technology, Perylene
Abstract

International audience; A perylene diimide (PDI) flanked diketopyrrolopyrrole (DPP) π-conjugated small molecule has been synthesized through an efficient and sustainable direct heteroarylation protocol. When paired with the donor polymer PTB7-Th, air-processed and tested bulk-heterojunction (BHJ) organic solar cells (OSCs) achieved a high power conversion efficiency (PCE) of 5.6%. The new acceptor showed favorable morphological changes upon solvent vapor annealing leading to a near 3-fold increase in PCE. This result is among the best reported utilizing DPP-based acceptors in air-processed and tested OSCs. All solar cells exhibited good air and light stability over a 35-day evaluation period.

Published
2017
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28. Effect of side chains on the electronic and photovoltaic properties of diketopyrrolopyrrole-based molecular acceptors

Author

Clément Cabanetos, Seth M. McAfee, Philippe Blanchard, Pierre Josse, Jean Roncali, Sylvie Dabos-Seignon, Gregory C. Welch, Antoine Labrunie, Clément Dalinot, MOLTECH-Anjou, Institut de Chimie du CNRS (INC)-Université d'Angers (UA)-Centre National de la Recherche Scientifique (CNRS), Department of Chemistry, University of Calgary, University of Calgary, Université d'Angers (UA)-Centre National de la Recherche Scientifique (CNRS), and Chimie, Ingénierie Moléculaire et Matériaux d'Angers (CIMMA)

Subjects
Materials science, Absorption spectroscopy, Organic solar cell, Bulk heterojunction, 02 engineering and technology, 010402 general chemistry, Photochemistry, 7. Clean energy, 01 natural sciences, Polymer solar cell, Biomaterials, Phthalimide, chemistry.chemical_compound, Materials Chemistry, Side chain, [CHIM]Chemical Sciences, Organic chemistry, diketopyrrolopyrrole, Electrical and Electronic Engineering, Inverted solar cell, ComputingMilieux_MISCELLANEOUS, Alkyl, chemistry.chemical_classification, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Molecular acceptor, General Chemistry, Electron acceptor, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 0104 chemical sciences, Electronic, Optical and Magnetic Materials, chemistry, Organic photovoltaics, Cyclic voltammetry, 0210 nano-technology
Abstract

International audience; Four molecular electron acceptors based on a common phthalimide end-capped diketopyrrolopyrrole pconjugated backbone, solubilized by different alkyl groups, have been synthesized. The influence of the nature and position of the solubilizing alkyl chains attached at the three constitutive blocks has been investigated. Results collected from UV-Vis absorption spectroscopy, cyclic voltammetry, solar cells fabrication and testing as well as atomic force microscopy show that the mode of substitution has negligible effect at the molecular level but strongly affects the material self-assembling properties, charge carrier transport and in turn, devices performances.

Published
2016
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29. Donor or Acceptor? How Selection of the Rylene Imide End Cap Impacts the Polarity of π-Conjugated Molecules for Organic Electronics

Author

Pierre Josse, Chad Risko, Abby-Jo Payne, Seth M. McAfee, Shi Li, Clément Cabanetos, Gregory C. Welch, Benoît H. Lessard, Nicole A. Rice, Department of Chemistry, University of Calgary, University of Calgary, School of Economics and Business, Beijing Normal University (BNU), MOLTECH-Anjou, Université d'Angers (UA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), School of Chemistry and Biochemistry, and Center for Organic Electronics and Photonics, Georgia Institute of Technology [Atlanta], Institute for Computer Graphics and Vision [Graz] (ICG), and Graz University of Technology [Graz] (TU Graz)

Subjects
Organic electronics, chemistry.chemical_classification, Organic solar cell, Energy Engineering and Power Technology, 02 engineering and technology, [CHIM.MATE]Chemical Sciences/Material chemistry, Conjugated system, 010402 general chemistry, 021001 nanoscience & nanotechnology, Photochemistry, 01 natural sciences, Acceptor, 0104 chemical sciences, chemistry.chemical_compound, chemistry, Diimide, Materials Chemistry, Electrochemistry, Chemical Engineering (miscellaneous), Electrical and Electronic Engineering, 0210 nano-technology, Imide, Perylene, Alkyl, ComputingMilieux_MISCELLANEOUS
Abstract

Three molecular semiconductors are compared and evaluated in organic field-effect transistors and organic solar cells. The molecules are constructed from the dyes diketopyrrolopyrrole (DPP), perylene diimide (PDI), and N-(alkyl)benzothioxanthene-3,4-dicarboximide (BTXI). The compound PDI–DPP–PDI (1) has previously been reported and used as a nonfullerene acceptor. The compounds PDI–DPP–BTXI (2) and BTXI–DPP–BTXI (3) were synthesized using direct (hetero)arylation methods and fully identified using NMR spectroscopy and mass spectrometry. All three compounds were characterized using UV–visible spectroscopy, cyclic voltammetry, and density functional theory calculations. Increasing the BTXI content results in a progressive destabilization of the electronic energy levels. For all compounds, no significant changes in the optical absorption spectra are observed when compared to a combination of the constituent optical absorption spectra. Compound 1 exhibits electron transport characteristics and functions as an...

Published
2018
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30. Scandium Alkyl and Hydride Complexes Supported by a Pentadentate Diborate Ligand: Reactions with CO2 and N2O

Author

Benjamin S. Gelfand, Warren E. Piers, Iker del Rosal, Daniel W. Beh, Laurent Maron, Jian-Bin Lin, Chris Gendy, Department of Chemistry, University of Calgary, University of Calgary, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-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), 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 sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), NSERC of Canada (Discovery Grant) the Canada Research Chair secretariat (Tier I CRC 2013-2020), and HPCs CALcul en Midi-Pyrenees (CALMIP-EOS) [1415]

Subjects
chemistry.chemical_classification, 010405 organic chemistry, Hydride, Chemistry, Dimer, Alkylation, Borane, 010402 general chemistry, 01 natural sciences, Medicinal chemistry, Dissociation (chemistry), Transition state, 0104 chemical sciences, Inorganic Chemistry, chemistry.chemical_compound, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Sigma bond, Alkyl
Abstract

Alkyl and hydrido scandium complexes of the dianionic pentatdentate ligand B2Pz4Py are reported. The key starting material (B2Pz4Py)ScCl is readily prepared and alkylated with organolithium reagents RLi (R = CH3, CH2SiMe3, CH2SiMe2Ph, CH2CH2CH3 and CH2CHMe2) to form alkyl derivatives in 61-93% yields. These compounds are very thermally stable and do not undergo sigma bond metathesis reactions with dihydrogen. The hydrido complex was prepared from (B2Pz4Py)ScCl and NaHBEt3 in 80% yield and was found to be more stable by 28 kcal mol-1 as a dimer, rather than a monomeric hydrido complex. However, the monomer is accessible through dissociation of the dimer at 80˚C. All of the compounds (B2Pz4Py)ScR react with water to form the bridging oxo dimer (B2Pz4Py)ScOSc(B2Pz4Py). The reactivity of the hydrido and methyl complexes towards carbon dioxide was explored; heating to 80˚C results in the formation of k2 formato and acetate complexes, respectively. The mechanisms were studied via density function theory and distinct transition states for insertion of CO2 into the Sc-R (R = H, CH3) were found, with the insertion into the Sc-CH3 being more enthalpically difficult (by 18 kcal mol-1) than insertion into Sc-H. The slow rate of reaction between [(B2Pz4Py)ScH]2 and CO2 is attributed to the barrier associated with dimer dissociation. In both insertion reactions, the kinetic products are k1 formato or acetate complexes that are only slightly less stable than the observed k2 derivatives. The k1 compounds can therefore be trapped by treating the k2 isomers with tris-pentafluorophenyl borane.

Published
2018
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31. Direct (Hetero)Arylation Polymerization of a Spirobifluorene and a Dithienyl-Diketopyrrolopyrrole Derivative: New Donor Polymers for Organic Solar Cells

Author

Shiming Zhang, Yangqian Zhang, Philippe Blanchard, Clément Cabanetos, Sergey V. Dayneko, Sylvie Dabos-Seignon, Gregory C. Welch, Pierre Josse, MOLTECH-Anjou, Université d'Angers (UA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Department of Chemistry, University of Calgary, University of Calgary, Nanjing Tech University, and Université d'Angers (UA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, Organic solar cell, direct (hetero)arylation polymerization, Polymers, Pharmaceutical Science, 02 engineering and technology, Conjugated system, 010402 general chemistry, Microscopy, Atomic Force, 01 natural sciences, 7. Clean energy, Polymer solar cell, Article, Analytical Chemistry, Catalysis, Polymerization, lcsh:QD241-441, chemistry.chemical_compound, lcsh:Organic chemistry, Drug Discovery, Solar Energy, Molecule, [CHIM]Chemical Sciences, Pyrroles, Physical and Theoretical Chemistry, diketopyrrolopyrrole, spirobifluorene, ComputingMilieux_MISCELLANEOUS, chemistry.chemical_classification, Fluorenes, Molecular Structure, Spectrum Analysis, Organic Chemistry, organic photovoltaics, Polymer, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, Combinatorial chemistry, 0104 chemical sciences, [CHIM.POLY]Chemical Sciences/Polymers, chemistry, Chemistry (miscellaneous), Molecular Medicine, 0210 nano-technology, Derivative (chemistry)
Abstract

International audience; The synthesis and preliminary evaluation as donor material for organic photovoltaics of the poly(diketopyrrolopyrrole-spirobifluorene) (PDPPSBF) is reported herein. Prepared via homogeneous and heterogeneous direct (hetero)arylation polymerization (DHAP), through the use of different catalytic systems, conjugated polymers with comparable molecular weights were obtained. The polymers exhibited strong optical absorption out to 700 nm as thin-films and had appropriate electronic energy levels for use as a donor with PC70BM. Bulk heterojunction solar cells were fabricated giving power conversion efficiencies above 4%. These results reveal the potential of such polymers prepared in only three steps from affordable and commercially available starting materials

Published
2018
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33. Facile hydrogen atom transfer to iron(<scp>iii</scp>) imido radical complexes supported by a dianionic pentadentate ligand

Author

Christos E. Kefalidis, Michael L. Neidig, Warren E. Piers, Stephanie H. Carpenter, Denis M. Spasyuk, Laurent Maron, Department of Chemistry, University of Calgary, University of Calgary, Department of Chemistry [Rochester], University of Rochester [USA], Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-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), 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 sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Institut National Polytechnique (Toulouse) (Toulouse INP), 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)-Institut National Polytechnique (Toulouse) (Toulouse INP), and Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)

Subjects
010405 organic chemistry, Ligand, Radical, General Chemistry, Hydrogen atom, 010402 general chemistry, Photochemistry, 01 natural sciences, 0104 chemical sciences, chemistry.chemical_compound, chemistry, Yield (chemistry), Polymer chemistry, Mössbauer spectroscopy, [CHIM]Chemical Sciences, Derivative (chemistry)
Abstract

International audience; A dianionic tetrapodal pentadentate diborate ligand is introduced. This ligand forms a high spin neutral iron(II) complex that reacts with a variety of organoazides to yield transient Fe(III) imido radicals that are extremely potent hydrogen atom abstractors. The nature of these species is supported by full characterization of the Fe(III) amido products, kinetic studies, density functional computations and Mössbauer spectroscopy on the –C6H4-p-tBu substituted derivative.

Published
2016
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34. Oxygen-Oxygen Bond Cleavage and Formation in Co(II)-Mediated Stoichiometric O-2 Reduction via the Potential Intermediacy of a Co(IV) Oxyl Radical

Author

Denis M. Spasyuk, Warren E. Piers, Laura Fairburn, Laurent Maron, Lucie Nurdin, Department of Chemistry, University of Calgary, University of Calgary, Canadian Light Source Inc., University of Saskatchewan [Saskatoon] (U of S), Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-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), 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 sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Natural Sciences and Engineering Research Council of Canada, French CNRS PICS project, Alberta Innovates Technology Futures, and Vanier Canada Graduate Scholarships

Subjects
010405 organic chemistry, Ligand, Dimer, chemistry.chemical_element, Protonation, General Chemistry, 010402 general chemistry, Photochemistry, 7. Clean energy, 01 natural sciences, Biochemistry, Oxygen, Catalysis, 0104 chemical sciences, Metal, chemistry.chemical_compound, Colloid and Surface Chemistry, chemistry, visual_art, visual_art.visual_art_medium, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Metal aquo complex, Bond cleavage
Abstract

International audience; In reactions of significance to alternative energy schemes, metal catalysts are needed to overcome kinetically and thermodynamically difficult processes. Often, high-oxidation-state, high-energy metal oxo intermediates are proposed as mediators in elementary steps involving O-O bond cleavage and formation, but the mechanisms of these steps are difficult to study because of the fleeting nature of these species. Here we utilized a novel dianionic pentadentate ligand system that enabled a detailed mechanistic investigation of the protonation of a cobalt(III)-cobalt(III) peroxo dimer, a known intermediate in oxygen reduction catalysis to hydrogen peroxide. It was shown that double protonation occurs rapidly and leads to a low-energy O-O bond cleavage step that generates a Co(III) aquo complex and a highly reactive Co(IV) oxyl cation. The latter was probed computationally and experimentally implicated through chemical interception and isotope labeling experiments. In the absence of competing chemical reagents, it dimerizes and eliminates dioxygen in a step highly relevant to O-O bond formation in the oxygen evolution step in water oxidation. Thus, the study demonstrates both facile O-O bond cleavage and formation in the stoichiometric reduction of O-2 to H2O with 2 equiv of Co(II) and suggests a new pathway for selective reduction of O-2 to water via Co(III)-O-O-Co(III) peroxo intermediates.

Published
2018
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35. Bromination of the benzothioxanthene Bloc: toward new π-conjugated systems for organic electronic applications

Author

Renaud Demadrille, Sergey V. Dayneko, Gregory C. Welch, Antoine Labrunie, Sylvie Dabos-Seignon, Clément Cabanetos, Damien Joly, Philippe Blanchard, Pierre Josse, Shi Li, Chad Risko, Benjamin Siegler, Magali Allain, MOLTECH-Anjou, Université d'Angers (UA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), School of Economics and Business, Beijing Normal University (BNU), Department of Chemistry, University of Calgary, University of Calgary, Université de Bordeaux (UB), Propriétés Optiques des Matériaux et Applications (POMA), Centre National de la Recherche Scientifique (CNRS)-Université d'Angers (UA), Chimie, Ingénierie Moléculaire et Matériaux d'Angers (CIMMA), Université d'Angers (UA)-Centre National de la Recherche Scientifique (CNRS), Plateforme d'ingénierie et Analyses moléculaires, Université d'Angers (UA), SYstèmes Moléculaires et nanoMatériaux pour l’Energie et la Santé (SYMMES), Institut de Chimie du CNRS (INC)-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), School of Chemistry and Biochemistry, and Center for Organic Electronics and Photonics, Georgia Institute of Technology [Atlanta], Universität Bielefeld = Bielefeld University, Chimie Et Interdisciplinarité : Synthèse, Analyse, Modélisation (CEISAM), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Laboratoire de Mécanique et de Rhéologie (LMR), Université de Tours-Polytech'Tours-Institut National des Sciences Appliquées - Centre Val de Loire (INSA CVL), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA), Synthèse, Structure et Propriétés de Matériaux Fonctionnels (STEP), 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)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Centre National de la Recherche Scientifique (CNRS)-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)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Centre National de la Recherche Scientifique (CNRS), Institute for Computer Graphics and Vision [Graz] (ICG), Graz University of Technology [Graz] (TU Graz), Institut de Chimie du CNRS (INC)-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 de Nantes (UN)-Université de Nantes (UN)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Halogenation, 02 engineering and technology, General Chemistry, [CHIM.MATE]Chemical Sciences/Material chemistry, Conjugated system, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, Combinatorial chemistry, Polymer solar cell, 0104 chemical sciences, chemistry.chemical_compound, chemistry, Materials Chemistry, [CHIM]Chemical Sciences, Palladium-catalyzed coupling reactions, 0210 nano-technology, Derivative (chemistry), ComputingMilieux_MISCELLANEOUS
Abstract

A selective and efficient method to afford a monobrominated benzothioxanthene (Br-BTXI) derivative is reported. Br-BTXI was extensively employed in common palladium catalyzed coupling reactions. Finally, as a proof of concept, a BTXI based molecular donor was synthesized and evaluated in bulk heterojunction solar cells.

Published
2018
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36. Photoactive Materials for Organic Solar Cells

Author

Welch, Gregory, Mcafee, Seth, Payne, Abby-Jo, Cabanetos, Clément, Josse, Pierre, Blanchard, Philippe, Department of Chemistry, University of Calgary, University of Calgary, MOLTECH-Anjou, Institut de Chimie du CNRS (INC)-Université d'Angers (UA)-Centre National de la Recherche Scientifique (CNRS), Université d'Angers (UA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Cabanetos, Clément

Subjects
[CHIM] Chemical Sciences, [CHIM]Chemical Sciences, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2017

37. Thiophene vs thiazole: Effect of the π-connector on the properties of phthalimide end-capped diketopyrrolopyrrole based molecular acceptors for organic photovoltaics

Author

Patricia Chávez, Denis Tondelier, Clément Cabanetos, Philippe Blanchard, Chloé Dindault, Sylvie Dabos-Seignon, Nicolas Leclerc, Clément Dalinot, Seth M. McAfee, Gregory C. Welch, Pierre Josse, MOLTECH-Anjou, Université d'Angers (UA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de chimie et procédés pour l'énergie, l'environnement et la santé (ICPEES), Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de physique des interfaces et des couches minces [Palaiseau] (LPICM), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Department of Chemistry, University of Calgary, University of Calgary, Ecole nationale supérieure de chimie, polymères et materiaux de strasbourg (ECPM), Institut de Chimie du CNRS (INC)-Université d'Angers (UA)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), and Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
chemistry.chemical_classification, Materials science, Organic solar cell, Process Chemistry and Technology, General Chemical Engineering, Chemical modification, 02 engineering and technology, [CHIM.MATE]Chemical Sciences/Material chemistry, Electron acceptor, 010402 general chemistry, 021001 nanoscience & nanotechnology, Ring (chemistry), Photochemistry, 01 natural sciences, 7. Clean energy, 0104 chemical sciences, Phthalimide, chemistry.chemical_compound, chemistry, Thiophene, [CHIM]Chemical Sciences, 0210 nano-technology, Thiazole, ComputingMilieux_MISCELLANEOUS
Abstract

Two phthalimide end-capped diketopyrrolopyrrole based non-fullerene derivatives distinguished by the nature of the π-conjugated connector namely a thiophene or a thiazole ring were synthesized via direct arylation and evaluated as electron acceptor materials in air-processed inverted organic solar cells. It turns out that this simple chemical modification significantly impacts the energetics, the charge transport properties and consequently the photovoltaic performances.

Published
2017
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38. Reactions of Neutral Cobalt(II) Complexes of a Dianionic Tetrapodal Pentadentate Ligand: Cobalt(III) Amides from Imido Radicals

Author

Nurdin, Lucie, Spasyuk, Denis M., Piers, Warren E., Maron, Laurent, Department of Chemistry, University of Calgary, University of Calgary, Canadian Light Source, University of Saskatchewan [Saskatoon] (U of S), Laboratoire de physique et chimie des nano-objets (LPCNO), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Institut National Polytechnique (Toulouse) (Toulouse INP), 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)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-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), 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 sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS]Physics [physics], [CHIM]Chemical Sciences
Abstract

bibtex: ISI:000398426000046 bibtex\location:'1155 16TH ST, NW, WASHINGTON, DC 20036 USA',publisher:'AMER CHEMICAL SOC',type:'Article',affiliation:'Piers, WE (Reprint Author), Univ Calgary, Dept Chem, 2500 Univ Dr NW, Calgary, AB T2N 1N4, Canada. Maron, L (Reprint Author), Univ Toulouse, LPCNO, INSA, UPS, 135 Ave Rangueil, F-31077 Toulouse, France. Maron, L (Reprint Author), CNRS, LPCNO, F-31077 Toulouse, France. Nurdin, Lucie; Spasyuk, Denis M.; Piers, Warren E., Univ Calgary, Dept Chem, 2500 Univ Dr NW, Calgary, AB T2N 1N4, Canada. Maron, Laurent, Univ Toulouse, LPCNO, INSA, UPS, 135 Ave Rangueil, F-31077 Toulouse, France. Maron, Laurent, CNRS, LPCNO, F-31077 Toulouse, France. Spasyuk, Denis M., Canadian Light Source Inc, 44 Innovat Blvd, Saskatoon, SK S7N 2V3, Canada.','author-email':'wpiers@ucalgary.ca laurent.maron@irsamc.ups-tlse.fr',da:'2018-12-05','doc-delivery-number':'EQ9SR',eissn:'1520-510X','funding-acknowledgement':'NSERC of Canada; The Alexander von Humboldt Foundation; Chinese Academy of Science; Institut Universitaire de France; CNRS; University of Calgary for an Eyes High Postdoctoral Fellowship; Alberta Innovates Technology Futures for Scholarship','funding-text':'Funding for this work was provided by NSERC of Canada (Discovery Grant) the Canada Research Chair secretariat (Tier I CRC 2013-2020) to W.E.P. The Alexander von Humboldt Foundation (W.E.P.and L.M.) and the Chinese Academy of Science (L.M.) are acknowledged for financial support. L.M. is member of the Institut Universitaire de France. L.M. and W.P. also acknowledge CNRS for a bilateral grant through the PICS Program. CalMip is acknowledged for a generous grant of computing time. D.M.S. thanks the University of Calgary for an Eyes High Postdoctoral Fellowship. L.N. thanks Alberta Innovates Technology Futures for Scholarship support. Dr. David W. Bi is acknowledged for collecting the X-ray data for compounds 1, 2-tBu, and 4.','journal-iso':'Inorg. Chem.','keywords-plus':'TRANSITION-METAL-COMPLEXES; COUPLED ELECTRON-TRANSFER; H BOND ACTIVATION; OLEFIN AZIRIDINATION; GENERATING HYDROGEN; OXOIRON(IV) COMPLEX; CRYSTAL-STRUCTURES; ATOM ABSTRACTION; WATER OXIDATION; REACTIVITY','number-of-cited-references':'61','orcid-numbers':'Piers, Warren/0000-0003-2278-1269','research-areas':'Chemistry','times-cited':'7','unique-id':'ISI:000398426000046','usage-count-last-180-days':'6','usage-count-since-2013':'25','web-of-science-categories':'Chemistry, Inorganic & Nuclear'\; Neutral cobalt(II) complexes of the dianionic tetrapodal pentadentate ligand B(2)Pz(4)Py, in which borate linkers supply the dianionic [GRAPHIC] charges, are repotted. Both the six-coordinate THF adduct 1-THF and the five-coordinate THF-free complex 1 are in a high-spin S = 3/2 configuration in the ground state and have been structurally characterized by X-ray crystallography. These two Co(II) starting materials react rapidly with aryl azides of moderate steric bulk. The thermodynamic products of these reactions are low-spin, diamagnetic, Co(III) amido complexes that are either monomeric, when an external hydrogen atom source such as 1,4-cydohexadiene is Present, or dimeric products formed via C-C coupling of the azide aryl group and internal transfer of H-. to the nitrogen. These products are fully characterized and are tare, examples of octahedral CO amid compounds; structural determinations reveal significant pytarrndalization of the amido nitrogens due to pi-pi repulsion wherein the amido is primarily a sigma donor. The amido products arise from highly reactive Co(III) imido radical intermediates that are the kinetic products of the reactions of 1 or 1-THF with the azide reagents. The imido radicals, can be detected by X-band EPR spectroscopy and have been probed by density functional theory computations, which indicate that this doublet species is characterized by a high degree of spin localization on the imido ligand, accounting for the reactivity with hydrogen atom sources and dimerization chemistry observed. The high coordination number and the electron rich nature of the dianionic B(2)Pz(4)Py ligand framework render the imido ligand formed highly reactive.

Published
2017

39. Carbon Monoxide Activation via O-Bound CO Using Decamethylscandocinium–Hydridoborate Ion Pairs

Author

Odile Eisenstein, Warren E. Piers, Laurent Maron, Ludovic Castro, Andreas Berkefeld, Masood Parvez, Department of Chemistry, University of Calgary, University of Calgary, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut de Chimie de Toulouse (ICT-FR 2599), Institut National Polytechnique (Toulouse) (Toulouse INP), 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)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-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), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-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), 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 sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), and Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
010405 organic chemistry, Hydride, chemistry.chemical_element, General Chemistry, Borane, 010402 general chemistry, Photochemistry, 01 natural sciences, Biochemistry, Medicinal chemistry, Catalysis, 0104 chemical sciences, Adduct, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, chemistry.chemical_compound, Colloid and Surface Chemistry, chemistry, Yield (chemistry), [CHIM.COOR]Chemical Sciences/Coordination chemistry, Scandium, Isomerization, Carbon, Carbon monoxide
Abstract

International audience; Ion pairs [Cp*2Sc]+[HB(p-C6F4R)3]− (R = F, 1-F; R = H, 1-H) were prepared and shown to be unreactive toward D2 and α-olefins, leading to the conclusion that no back-transfer of hydride from boron to scandium occurs. Nevertheless, reaction with CO is observed to yield two products, both ion pairs of the [Cp*2Sc]+ cation with formylborate (2-R) and borataepoxide (3-R) counteranions. DFT calculations show that these products arise from the carbonyl adduct of the [Cp*2Sc]+ in which the CO is bonded to scandium through the oxygen atom, not the carbon atom. The formylborate 2-R is formed in a two-step process initiated by an abstraction of the hydride by the carbon end of an O-bound CO, which forms an η2-formyl intermediate that adds, in a second step, the borane at the carbon. The borataepoxide 3-R is suggested to result from an isomerization of 2-R. This unprecedented reaction represents a new way to activate CO via a reaction channel emanating from the ephemeral isocarbonyl isomer of the CO adduct.

Published
2012
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40. Probing protein interactions with hydrogen/deuterium exchange and mass spectrometry—A review

Author

Martial Rey, David C. Schriemer, Andrew J. Percy, Kyle M. Burns, Department of Chemistry, University of Calgary, University of Calgary, and Department of Biochemistry and Molecular Biology (BMB)

Subjects
MESH: Pharmaceutical Preparations, Analytical chemistry, High resolution, Mass spectrometry, 01 natural sciences, Biochemistry, Mass Spectrometry, Analytical Chemistry, Protein–protein interaction, 03 medical and health sciences, Computational chemistry, [SDV.BBM.GTP]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Genomics [q-bio.GN], Protein Interaction Mapping, MESH: Protein Binding, Environmental Chemistry, Limited capacity, MESH: Proteins, [SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology, Spectroscopy, 030304 developmental biology, MESH: Mass Spectrometry, 0303 health sciences, Chemistry, MESH: Protein Interaction Mapping, 010401 analytical chemistry, Deuterium Exchange Measurement, Proteins, 0104 chemical sciences, [SDV.BBM.BS]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biomolecules [q-bio.BM], Pharmaceutical Preparations, MESH: Deuterium Exchange Measurement, Structural biology, Hydrogen–deuterium exchange, Chemical labeling, Protein Binding
Abstract

International audience; Assessing the functional outcome of protein interactions in structural terms is a goal of structural biology, however most techniques have a limited capacity for making structure-function determinations with both high resolution and high throughput. Mass spectrometry can be applied as a reader of protein chemistries in order to fill this void, and enable methodologies whereby protein structure-function determinations may be made on a proteome-wide level. Protein hydrogen/deuterium exchange (H/DX) offers a chemical labeling strategy suitable for tracking changes in "dynamic topography" and thus represents a powerful means of monitoring protein structure-function relationships. This review presents the exchange method in the context of interaction analysis. Applications involving interface detection, quantitation of binding, and conformational responses to ligation are discussed, and commentary on recent analytical developments is provided.

Published
2012
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41. A triazatruxene-based molecular dyad for single-component organic solar cells

Author

Martin Blais, Giacomo Londi, Philippe Blanchard, Clément Cabanetos, Sergey V. Dayneko, Sylvie Dabos-Seignon, Gregory C. Welch, Antoine Labrunie, David Beljonne, MOLTECH-Anjou, Université d'Angers (UA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Department of Chemistry 'Ugo Schiff', Università degli Studi di Firenze = University of Florence [Firenze] (UNIFI), Department of Chemistry, University of Calgary, University of Calgary, Institute for Computer Graphics and Vision [Graz] (ICG), Graz University of Technology [Graz] (TU Graz), and Université de Mons (UMons)

Subjects
Materials science, Organic solar cell, Single component, [CHIM.MATE]Chemical Sciences/Material chemistry, 02 engineering and technology, General Medicine, 010402 general chemistry, 021001 nanoscience & nanotechnology, Photochemistry, 01 natural sciences, Triazatruxene, 0104 chemical sciences, 0210 nano-technology, ComputingMilieux_MISCELLANEOUS
Abstract

The synthesis, characterization and use of a new donor-acceptor molecular dyad in single component organic solar cells are reported. The dyad, composed of a triazatruxene-based push-pull 'donor' unit linked to a C60 'acceptor' unit through a non-conjugated σ connector, led to promising power conversion efficiencies of 0.6% when embedded in simple devices exhibiting the architecture: indium tin oxide (ITO)/poly(3,4-ethylenedioxythiophene): polystyrene sulfonic acid (PEDOT:PSS)/dyad/Al.

Published
2018
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42. High-throughput photocontrol of water drop generation, fusion, and mixing in a dual flow-focusing microfluidic device

Author

Nurdin, Lucie, Venancio-Marques, Anna, Rudiuk, Sergii, Morel, Mathieu, Baigl, Damien, Department of Chemistry, University of Calgary, University of Calgary, Processus d'Activation Sélective par Transfert d'Energie Uni-électronique ou Radiatif (UMR 8640) (PASTEUR), Département de Chimie - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[CHIM.GENI]Chemical Sciences/Chemical engineering, Azobenzene, Mixing, AzoTAB, Surfactant, Microfluidics, Photocontrol, Drop
Abstract

International audience; We describe the first method to control, in a single microfluidic device, the generation, fusion, and mixing of pico- to nanoliter water-in-oil drops using a straightforward LED light stimulus. This is achieved by implementing a photosensitive surfactant in the water phases of a novel dual flow-focusing microfluidic configuration. UV illumination at 365 nm enables dynamic switch of the flow behavior between a stable dual jet regime (−UV) and a stable dual drop regime (+UV), thus allowing us to generate on-demand two distinct populations of water drops. These drops are fused and mixed downstream inside expansion chambers, offering both a dynamic control by light stimulation and a controllable degree of fusion and mixing by the positions of chambers. The mixing inside the fused drops is found to be much faster than diffusion due to the chaotic advection inside the moving drops.; Grâce à l’introduction d’un tensioactif photosensible dans les phases aqueuses d’un nouveau type de dispositif microfluidique à double focalisation de flux, nous décrivons pour la première fois le contrôle de la génération, de la fusion et du mélange de microgouttes aqueuses dispersées dans une phase d’huile, à l’aide d’un stimulus lumineux produit par une simple diode électroluminescente. Une illumination UV à 365 nm fait basculer réversiblement l’écoulement entre un régime à double jet (−UV) et un régime à double train de gouttes (+UV), nous permettant ainsi de générer à la demande, et de manière dynamique, deux populations de gouttes de compositions distinctes. Des chambres d’expansion permettent d’induire la fusion des gouttes générées par la lumière et de contrôler ainsi le mélange de leurs composants. Nous montrons que la position des chambres définit le degré de fusion et de mélange. Ce mélange s’opère de manière bien plus rapide que le temps caractéristique de diffusion des composants, grâce à l’advection chaotique créée au sein des gouttes en mouvement.

Published
2016
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43. The Optimization of Direct Heteroarylation and Sonogashira Cross-Coupling Reactions as Efficient and Sustainable Synthetic Methods To Access π-Conjugated Materials with Near-Infrared Absorption

Author

Gregory C. Welch, Pierre Josse, Seth M. McAfee, Jonathan Cann, P. Blanchard, Clément Cabanetos, Department of Chemistry, University of Calgary, University of Calgary, MOLTECH-Anjou, and Université d'Angers (UA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Organic solar cell, General Chemical Engineering, Sonogashira coupling, chemistry.chemical_element, 02 engineering and technology, Conjugated system, 010402 general chemistry, Photochemistry, 01 natural sciences, Coupling reaction, Heterogeneous catalyst, chemistry.chemical_compound, C−H Bond activation, Thiophene, Environmental Chemistry, Molecule, [CHIM]Chemical Sciences, Organic electronics, Renewable Energy, Sustainability and the Environment, General Chemistry, 021001 nanoscience & nanotechnology, Thienoisoindigo, 0104 chemical sciences, Direct heteroarylation, chemistry, near-ir absorption, Sustainable synthesis, 0210 nano-technology, Palladium
Abstract

International audience; Two π-conjugated thienoisoindigo-based organic small molecules have been designed to be synthetically accessible through sustainable direct heteroarylation or Sonogashira C–C bond forming cross-coupling reactions utilizing a heterogeneous palladium catalyst. To access these materials, one molecule, TII-ThNaph2, contains a thiophene π-bridge to facilitate direct heteroarylation protocols, whereas the other, TII-AcNaph2, contains an acetylene π-bridge required for Sonogashira couplings. The synthetic route to both final materials was optimized to investigate the reactivity of thienoisoindigo, which to this point has not been significantly explored in comparison to other popular organic dyes such as diketopyrrolopyrrole and isoindigo. Considering the reported interest of thienoisoindigo-based materials in organic solar cells and field-effect transistors, both final materials have been characterized for their optical, electrochemical and thermal properties offering a comparison of the structure–property relationships that manifest as a result of the two different π-bridging units.

Published
2016
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44. Carboxy-functionalized dithiolate di-iron complexes related to the active site of Fe-only hydrogenase

Author

Jean Talarmin, V. Vijaikanth, Jean-François Capon, François Y. Pétillon, Philippe Schollhammer, Frédéric Gloaguen, Department of Chemistry, University of Calgary, University of Calgary, Chimie, Electrochimie Moléculaires et Chimie Analytique (CEMCA), Institut Brestois Santé Agro Matière (IBSAM), and Université de Brest (UBO)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)

Subjects
Hydrogenase, biology, 010405 organic chemistry, Chemistry, Organic Chemistry, Active site, 010402 general chemistry, Electrochemistry, 01 natural sciences, Biochemistry, 0104 chemical sciences, 3. Good health, Inorganic Chemistry, Crystallography, Materials Chemistry, biology.protein, Molecule, [CHIM]Chemical Sciences, Physical and Theoretical Chemistry, Fe-only hydrogenase, Single crystal
Abstract

Reactions of the di-iron complex [Fe 2 (μ-S) 2 (CO) 6 ] 2− with carboxy-functionalized dihalide derivatives (XCH 2 ) 2 R (X = Cl, R = NC 6 H 4 CH 2 CO 2 CH 3 ; X = Br, R = C 6 H 3 COOH, C 6 H 3 COON(COCH 2 ) 2 ) gave new functionalized dithiolate di-iron complexes [Fe 2 (μ-SRS)(CO) 6 ] (R = (CH 2 ) 2 NC 6 H 4 CH 2 CO 2 CH 3 ( 1 ), (CH 2 ) 2 C 6 H 3 COOH ( 2 ), (CH 2 ) 2 C 6 H 3 COON(COCH 2 ) 2 ( 3 )) in low yields. The azadithiolate complex 1 has been characterized by a single crystal X-ray diffraction analysis and studied by electrochemical methods.

Published
2007
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45. Ab initio study of the (5R)- and (5S)-TT pyrimidine h5(6-4) pyrimidone photoproducts. Implications on the design of new biologically relevant analogues

Author

Pascale Clivio, Pascal Sonnet, Dominique Guillaume, François-Yves Dupradeau, Hans Martin Senn, Laboratoire des Glucides (LG), Université de Picardie Jules Verne (UPJV)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Agents infectieux, résistance et chimiothérapie - UR UPJV 4294 (AGIR ), Université de Picardie Jules Verne (UPJV)-CHU Amiens-Picardie, Institut de Chimie Moléculaire de Reims, Université de Reims Champagne-Ardenne (URCA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Department of Chemistry, University of Calgary, University of Calgary, Institut de Chimie des Substances Naturelles (ICSN), and Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Models, Molecular, Pyrimidine, Stereochemistry, Photochemistry, Ab initio, Substituent, Molecular Conformation, Pyrimidinones, Crystallography, X-Ray, chemistry.chemical_compound, symbols.namesake, [CHIM]Chemical Sciences, Molecule, Pyrimidone, Dihydrothymine, ComputingMilieux_MISCELLANEOUS, Molecular Structure, Chemistry, Organic Chemistry, Diastereomer, Computational Biology, Stereoisomerism, Pyrimidines, symbols, Thermodynamics, van der Waals force
Abstract

A computational study of a series of N 1 - and/or C 6 -alkyl-5,6-dihydrothymine diastereomers at theory levels up to MP4(SDTQ)/6-31G*//HF/6-31G* and MP2/6-311G**//HF/6-31G* has demonstrated the respective importance of the substituents at positions 1, 5, and 6 on the energetically favored conformation of each isomer. Results obtained both in the gas and condensed phase indicate that unsubstitution of the N 1 -position favors a half-chair conformation with the C 5 -and C 6 -substituents in the equatorial position. On the other hand, in the case of the (6S)-1,6-dimethyl-5,6-dihydrothymine, the C 6 -substituent adopts the axial position to minimize its van der Waals interactions with the N 1 -substituent. Furthermore, if the configuration at the C 5 -dihydrothymine position has no resultant influence on the total molecular free energy, when a pyrimidone substituent is introduced at the dihydrothymine C 6 -position, additional repulsive forces between the C 5 - and C 6 -substituents make the diaxially substituted half-chair conformation the most energetically favorable one. These results indicate that the observed C 6 -axially substituted conformation of the thymine-thymine pyrimidine h 5 (6-4) pyrimidone photoproducts is not necessarily induced by the macrocyclic structure. They also nicely explain the formation mechanism of these photoproduct derivatives, and allow the prediction of the conformation of new analogues.

Published
2002
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46. Decamethylscandocinium-hydrido-(perfluorophenyl)borate: fixation and tandem tris(perfluorophenyl)borane catalysed deoxygenative hydrosilation of carbon dioxide

Author

Andreas Berkefeld, Masood Parvez, Odile Eisenstein, Ludovic Castro, Warren E. Piers, Laurent Maron, Department of Chemistry, University of Calgary, University of Calgary, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-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), 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 sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut de Chimie de Toulouse (ICT-FR 2599), Institut National Polytechnique (Toulouse) (Toulouse INP), 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)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), and 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)

Subjects
010405 organic chemistry, Hydride, Inorganic chemistry, Ionic bonding, General Chemistry, Nuclear magnetic resonance spectroscopy, Borane, 010402 general chemistry, 01 natural sciences, Medicinal chemistry, Dissociation (chemistry), 0104 chemical sciences, Catalysis, chemistry.chemical_compound, chemistry, Electrophile, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Triethylsilane
Abstract

International audience; This work was directed at studying the capability of structurally defined, strongly Lewis-acidic metal centers to effect catalytic reductive fixation of the small molecule substrate CO2. Exposing solutions or solid samples of the ion pair [Cp*2Sc][HB(C6F5)3] 1CIP, in which the highly electrophilic decamethyl-scandocene cation and [HB(C6F5)]− as a potentially reactive source of hydride equivalents are associated, to CO2 selectively produces ion pair [Cp*2Sc][HCO2B(C6F5)3] 2CIP. The results of solution and solid state structural analysis of 2CIP imply ionic association of [Cp*2Sc]+ and [HCO2B(C6F5)3]− rather than B(C6F5)3-adduct formation to neutral Cp*2Sc-formate. In the presence of B(C6F5)3 co-catalyst and excess triethylsilane, the formation of 2CIP from 1CIP initiates the catalytic deoxygenative hydrosilation of CO2 to CH4. The roles of ion pairs 1 and 2, borane co-catalyst, and silane in the catalytic reaction were studied mechanistically by NMR spectroscopy. Intermediately formed 3,3,7,7-tetraethyl-3,7-disila-4,6-dioxanonane product was found to exert an accelerating effect on the overall reaction rate by promoting [HCO2B(C6F5)3]− dissociation to give 2SIP through formation of separated ion pairs [Cp*2Sc(κ2-(Et3SiO)2CH2)][HCO2{B(C6F5)3}n], n = 1, 2. DFT calculations show that the formation 2CIP from the reaction of 1CIP with CO2 is exoergic and without significant energy barriers. This work lays the basis for future studies of reactive ion pairs of this kind in the context of small molecule chemistry.

Published
2013
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47. High-throughput photocontrol of water drop generation, fusion, and mixing in a dual flow-focusing microfluidic device

Author

Mathieu Morel, Anna Venancio-Marques, Lucie Nurdin, Damien Baigl, Sergii Rudiuk, Department of Chemistry, University of Calgary, University of Calgary, Processus d'Activation Sélective par Transfert d'Energie Uni-électronique ou Radiatif (UMR 8640) (PASTEUR), Département de Chimie - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Chemistry(all), General Chemical Engineering, Microfluidics, LIGHT STIMULATION, 02 engineering and technology, Dynamic control, 010402 general chemistry, 01 natural sciences, Gouttes, Flow focusing, Optics, [CHIM.GENI]Chemical Sciences/Chemical engineering, Mixing, Surfactant, Mélange, Tensio-actifs, Fusion, Azobenzene, Chemistry, business.industry, Microfluidique, Drop (liquid), AzoTAB, Photocontrol, General Chemistry, Drop, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Chemical Engineering(all), Photocontrôle, 0210 nano-technology, business
Abstract

International audience; We describe the first method to control, in a single microfluidic device, the generation, fusion, and mixing of pico- to nanoliter water-in-oil drops using a straightforward LED light stimulus. This is achieved by implementing a photosensitive surfactant in the water phases of a novel dual flow-focusing microfluidic configuration. UV illumination at 365 nm enables dynamic switch of the flow behavior between a stable dual jet regime (−UV) and a stable dual drop regime (+UV), thus allowing us to generate on-demand two distinct populations of water drops. These drops are fused and mixed downstream inside expansion chambers, offering both a dynamic control by light stimulation and a controllable degree of fusion and mixing by the positions of chambers. The mixing inside the fused drops is found to be much faster than diffusion due to the chaotic advection inside the moving drops.; Grâce à l’introduction d’un tensioactif photosensible dans les phases aqueuses d’un nouveau type de dispositif microfluidique à double focalisation de flux, nous décrivons pour la première fois le contrôle de la génération, de la fusion et du mélange de microgouttes aqueuses dispersées dans une phase d’huile, à l’aide d’un stimulus lumineux produit par une simple diode électroluminescente. Une illumination UV à 365 nm fait basculer réversiblement l’écoulement entre un régime à double jet (−UV) et un régime à double train de gouttes (+UV), nous permettant ainsi de générer à la demande, et de manière dynamique, deux populations de gouttes de compositions distinctes. Des chambres d’expansion permettent d’induire la fusion des gouttes générées par la lumière et de contrôler ainsi le mélange de leurs composants. Nous montrons que la position des chambres définit le degré de fusion et de mélange. Ce mélange s’opère de manière bien plus rapide que le temps caractéristique de diffusion des composants, grâce à l’advection chaotique créée au sein des gouttes en mouvement.

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48. Therapeutic reduction of neurocan in murine intracerebral hemorrhage lesions promotes oligodendrogenesis and functional recovery.

Author

Li H, Ghorbani S, Oladosu O, Zhang P, Visser F, Dunn J, Zhang Y, Ling CC, Yong VW, and Xue M

Subjects
Animals, Mice, Male, Mice, Inbred C57BL, Disease Models, Animal, Cerebral Hemorrhage pathology, Cerebral Hemorrhage metabolism, Oligodendroglia metabolism, Oligodendroglia pathology, Oligodendroglia drug effects, Recovery of Function physiology, Recovery of Function drug effects, Neurocan
Abstract

Background: Intracerebral hemorrhage (ICH) causes prominent deposition of extracellular matrix molecules, particularly the chondroitin sulphate proteoglycan (CSPG) member neurocan. In tissue culture, neurocan impedes the properties of oligodendrocytes. Whether therapeutic reduction of neurocan promotes oligodendrogenesis and functional recovery in ICH is unknown., Methods: Mice were retro-orbitally injected with adeno-associated virus (AAV-CRISPR/Cas9) to reduce neurocan deposition after ICH induction by collagenase. Other groups of ICH mice were treated with vehicle or a drug that reduces CSPG synthesis, 4-4-difluoro-N-acetylglucosamine (difluorosamine). Rota-rod and grip strength behavioral tests were conducted over 7 or 14 days. Brain tissues were investigated for expression of neurocan by immunofluorescence microscopy and western blot analysis. Brain cryosections were also stained for microglia/macrophage phenotype, oligodendrocyte lineage cells and neuroblasts by immunofluorescence microscopy. Tissue structural changes were assessed using brain magnetic resonance imaging (MRI)., Results: The adeno-associated virus (AAV)-reduction of neurocan increased oligodendrocyte numbers and functional recovery in ICH. The small molecule inhibitor of CSPG synthesis, difluorosamine, lowered neurocan levels in lesions and elevated numbers of oligodendrocyte precursor cells, mature oligodendrocytes, and SOX2 + nestin + neuroblasts in the perihematomal area. Difluorosamine shifted the degeneration-associated functional state of microglia/macrophages in ICH towards a regulatory phenotype. MRI analyses showed better fiber tract integrity in the penumbra of difluorosamine mice. These beneficial difluorosamine results were achieved with delayed (2 or 3 days) treatment after ICH., Conclusion: Reducing neurocan deposition following ICH injury is a therapeutic approach to promote histological and behavioral recovery from the devastating stroke., Competing Interests: Declarations. Ethics approval and consent to participate: All animal experiments were performed with ethics approval (protocol number AC21-0073) from the Animal Care Committee at the University of Calgary under regulations of the Canadian Council of Animal Care. Consent for publication: Not applicable. Competing interests: PZ, CCL and VWY are co-inventors in a US Provisional Patent application (US 63/720,938) titled: Fluorinated glucosamine analogs to reduce injury and promote recovery in neurological disorders., (© 2025. The Author(s).)

Published
2025
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49. Retention behavior of Hg 2+ , MeHg + , thimerosal and phenylmercuric acetate on a C 18 RP-HPLC column.

Author

Le MVK, Pourzadi N, and Gailer J

Subjects
Chromatography, High Pressure Liquid methods, Phenylmercury Compounds chemistry, Humans, Spectrophotometry, Atomic methods, Thimerosal chemistry, Mercury chemistry, Mercury analysis, Methylmercury Compounds analysis, Methylmercury Compounds chemistry, Chromatography, Reverse-Phase methods
Abstract

Humans are exposed to potentially toxic mercuric mercury (Hg 2+ ) and methylmercury (MeHg + ) by the ingestion of food, to the bactericidal vaccine additive thimerosal (THI), and/or to the antifungal compound phenylmercuric acetate (PMA) which is used in some lens cleaning ophthalmic fluids. While numerous HPLC methods have been developed to separate Hg 2+ and MeHg + in environmental samples (e.g. food, surface waters), comparatively few have been reported for THI and PMA, in part owing to their increased hydrophobicity. We investigated the retention behavior of Hg 2+ , MeHg + , THI and PMA on a reversed-phase (RP) HPLC column using a flame atomic absorption spectrometer (FAAS) as a Hg-specific detector. Mobile phases comprised of 50 mM phosphate buffer (pH 7.4) with acetonitrile (ACN) concentrations of 30-50 % (v:v) produced single Hg-peaks, which eluted in the order THI, Hg 2+ , MeHg + and PMA. With the 50 % ACN mobile phase, all mercurials eluted within 5 min. While the utilization of a FAAS precludes the analysis of environmental waters with the developed RP-HPLC-FAAS method, the latter is useful to probe the stability of THI and PMA in the presence of physiologically relevant concentrations of salt (100 mM in blood plasma) and l-cysteine (0.5 mM in hepatocyte cytosol), which is important as both mercurials have been recently shown to effectively inhibit the main protease of SARS-CoV-2, though the actual inhibitory Hg-species is unknown., Competing Interests: Declaration of competing interest The authors declare no conflict of interest, (Copyright © 2024 Elsevier B.V. All rights reserved.)

Published
2025
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50. Unprecedented Cubic Mesomorphic Behaviour of Crown-Ether Functionalized Amphiphilic Cyclodextrins.

Author

Espejo J, Zellmann-Parrotta CO, Sarkar D, Che A, Michaelis VK, Williams VE, and Ling CC

Abstract

Amphiphilic supramolecular materials based on biodegradable cyclodextrins (CDs) have been known to self-assemble into different types of thermotropic liquid crystals, including smectic and hexagonal columnar mesophases. Previous studies on amphiphilic CDs bearing 14 aliphatic chains at the secondary face and 7 oligoethylene glycol (OEG) chains at the primary face showed that the stability of the mesophase can be rationally tuned through implementation of terminal functional groups to the OEG chains. Here, we report the syntheses of first examples of crown ether-functionalized amphiphilic cyclodextrins that unexpectedly form thermotropic bicontinuous cubic phases. This constitutes the first reported examples of cyclodextrins forming such phases, which are potentially capable of 3D ion transport. Lithium composites were made to assess lithium conduction in the material. XRD revealed the added lithium salt destabilizes the cubic phase in favour of the smectic phase. Solid-state NMR studies showed that these materials conduct lithium ions with a very low activation energy., (© 2024 The Author(s). Chemistry - A European Journal published by Wiley-VCH GmbH.)

Published
2024
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