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1. Synthesis of a New Co Metal–Organic Framework Assembled from 5,10,15,20-Tetrakis((pyridin-4-yl) phenyl)porphyrin 'Co-MTPhPyP' and Its Application to the Removal of Heavy Metal Ions

Author

Henry Arceo-Ruiz, Elba Xochitiotzi-Flores, Héctor García-Ortega, Norberto Farfán, Rosa Santillan, Susana Rincón, and Alejandro Zepeda

Subjects
metal–organic framework, porphyrin, cobalt, adsorption, lead, kinetic study, Organic chemistry, QD241-441
Abstract

The synthesis of a Co metal–organic framework assembled from 5,10,15,20-tetrakis((pyridin-4-yl)phenyl)porphyrin; TPhPyP) “Co-MTPhPyP” is reported. The TPhPyP ligand was synthesized via aldehyde condensation in 28% yield and characterized by 1H nuclear magnetic resonance (1H NMR), Fourier-transform infrared (FTIR), high-resolution mass spectrometry (HRMS), and UV-visible spectroscopy (UV-vis). Co-MTPhPyP was prepared by the solvothermal method from TPhPyP and CoCl2·H2O in 55% yield and characterized by X-ray powder diffraction (XRD), FTIR, thermogravimetric analysis (TGA), field-emission scanning electron microscopy with energy-dispersive X-ray (FESEM-EDS), X-ray photoelectron spectroscopy (XPS), and dynamic light scattering (DLS), showing a particle size distribution of 418 ± 58 nm. The sorption properties of the Co-MTPhPyP for the effective removal of Pb(II) and Cu(II) were evaluated in an aqueous medium and Cthe results showed uptake capacities of 383.4 and 168 mg of the metal g−1 after 2 h, respectively. Kinetic studies of Pb(II) adsorption by Co-MTPhPyP were adjusted to the pseudo-second-order model with a maximum adsorption capacity of 458.8 mg g−1 at 30 min of exposition.

Published
2023
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3. Multicomponent Click Synthesis of New 1,2,3-Triazole Derivatives of Pyrimidine Nucleobases: Promising Acidic Corrosion Inhibitors for Steel

Author

Rodrigo González-Olvera, Araceli Espinoza-Vázquez, Guillermo E. Negrón-Silva, Manuel E. Palomar-Pardavé, Mario A. Romero-Romo, and Rosa Santillan

Subjects
nucleobases, multicomponent reaction, 1,2,3-triazoles, acidic corrosion, steel, Organic chemistry, QD241-441
Abstract

A series of new mono-1,2,3-triazole derivatives of pyrimidine nucleobases were synthesized by one-pot copper(I)-catalyzed 1,3-dipolar cycloaddition reactions between N-1-propargyluracil and thymine, sodium azide and several benzyl halides. The desired heterocyclic compounds were obtained in good yields and characterized by NMR, IR, and high resolution mass spectrometry. These compounds were investigated as corrosion inhibitors for steel in 1 M HCl solution, using electrochemical impedance spectroscopy (EIS) technique. The results indicate that these heterocyclic compounds are promising acidic corrosion inhibitors for steel.

Published
2013
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4. Synthesis of New 1,2,3-Triazole Derivatives of Uracil and Thymine with Potential Inhibitory Activity against Acidic Corrosion of Steels

Author

Mario A. Romero-Romo, Manuel E. Palomar-Pardavé, Nidia Maldonado-Carmona, Araceli Espinoza-Vázquez, Deyanira Angeles-Beltrán, Rodrigo González-Olvera, Guillermo E. Negrón-Silva, and Rosa Santillan

Subjects
synthesis, triazoles, pyrimidines, biological, corrosion, Organic chemistry, QD241-441
Abstract

Ten 1,4-disubstituted 1,2,3-triazoles were synthesized from one of 1-(azido-methyl)benzene, 1-(azidomethyl)-4-fluorobenzene, 1-(azidomethyl)-4-chlorobenzene, 1-(azidomethyl)-4-bromobenzene or 1-(azidomethyl)-4-iodobenzene, generated in situ from sodium azide and the corresponding benzyl halide, and dipropargyl uracil or dipropargyl thymine. Optimal experimental conditions were established for the conventional click chemistry. The corrosion inhibiting properties of some of these compounds, which were determined by means of an electrochemical technique, are also presented.

Published
2013
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5. State of the Art of Boron and Tin Complexes in Second- and Third-Order Nonlinear Optics §

Author

Cristina C. Jiménez, Alejandro Enríquez-Cabrera, Oscar González-Antonio, Javier Ordóñez-Hernández, Pascal G. Lacroix, Pablo Labra-Vázquez, Norberto Farfán, and Rosa Santillan

Subjects
organoboron complex, organotin complex, nonlinear optics, two-photon absorption, Second-Harmonic Generation, Inorganic chemistry, QD146-197
Abstract

Boron and tin complexes have been a versatile and very interesting scaffold for the design of nonlinear optical (NLO) chromophores. In this paper we present a wide range of reports since the 1990s to date, which include second-order (e.g., second harmonic generation) and third-order (e.g., two-photon absorption) NLO properties. After a short introduction on the origin of the NLO response in molecules, the different features associated with the introduction of these inorganic motifs in the organic-based NLO materials are discussed: Their effect on the accepting/donating capabilities of the substituents, on the efficiency of the π-conjugated linkage, and on the topology of the chromophores which can be tuned from the first generation of “push-pull„ chromophores to more sophisticated two- or three-dimensional architectures.

Published
2018
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7. Crystal structure of N-[(E)-(1,3-benzodioxol-5-yl)methylidene]-4-chloroaniline

Author

J. Pablo García-Merinos, Yliana López, J. Betzabe González-Campos, Judit A. Aviña-Verduzco, Rosa E. del Río, and Rosa Santillan

Subjects
crystal structure, O...Cl contact, Schiff base, Crystallography, QD901-999
Abstract

In the title compound, C14H10ClNO2, obtained by the condensation of 4-chloroaniline and piperonal, the five-membered ring is almost planar (r.m.s. deviation = 0.023 Å) and the dihedral angle between the aromatic rings is 43.22 (14)°. In the crystal, a short O...Cl contact of 3.173 (2) Å is observed. The molecules are arranged into corrugated (010) layers.

Published
2014
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8. Multicomponent Synthesis and Evaluation of New 1,2,3-Triazole Derivatives of Dihydropyrimidinones as Acidic Corrosion Inhibitors for Steel

Author

Rodrigo González-Olvera, Viridiana Román-Rodríguez, Guillermo E. Negrón-Silva, Araceli Espinoza-Vázquez, Francisco Javier Rodríguez-Gómez, and Rosa Santillan

Subjects
multicomponent synthesis, dihydropyrimidinone, 1,2,3-triazole, corrosion inhibitor, steel, Organic chemistry, QD241-441
Abstract

An efficient one-pot synthesis of 1,2,3-triazole derivatives of dihydropyrimidinones has been developed using two multicomponent reactions. The aldehyde-1,2,3-triazoles were obtained in good yields from in situ-generated organic azides and O-propargylbenzaldehyde. The target heterocycles were synthesized through the Biginelli reaction in which the aldehyde-1,2,3-triazoles reacted with ethyl acetoacetate and urea in the presence of Ce(OTf)3 as the catalyst. The corrosion inhibition of steel grade API 5 L X52 in 1 M HCl by the synthesized compounds was investigated using the electrochemical impedance spectroscopy technique. The measurements revealed that these heterocycles are promising candidates to inhibit acidic corrosion of steel.

Published
2016
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9. (25R)-16β-Acetoxy-3β-bromo-23′,26-epoxy-23′,25-dimethyl-5α-cholest-23,23′-en-6-one dichloromethane monosolvate

Author

Susana Rincón, Rebeca Yépez, M. Eugenia Ochoa, Yliana López, Rosa Santillan, and Norberto Farfán

Subjects
Crystallography, QD901-999
Abstract

The crystal structure of the title compound, C31H45BrO5·CH2Cl2, prepared in six steps from diosgenin, confirmed that the configurations of the stereogenic centers, positions 20S and 25R, remain unchanged during the reaction. The six-membered A, B and C rings have chair conformations. The five-membered ring D has an envelope conformation (with the methyl-substituted C atom fused to ring C as the flap) and the six-membered dihydropyran ring E adopts a twist-boat conformation. In the crystal, molecules are linked via C—H...O and C—H...Cl hydrogen bonds, the latter involving the dichloromethane solvent molecule, forming a three-dimensional supramolecular network.

Published
2012
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10. Polymeric Encapsulate of Streptomyces Mycelium Resistant to Dehydration with Air Flow at Room Temperature

Author

María Elena Mancera-López, Josefina Barrera-Cortés, Roberto Mendoza-Serna, Armando Ariza-Castolo, and Rosa Santillan

Subjects
actinomycetes, alginate capsules, drying treatment, rotary drum, vegetative cells, Polymers and Plastics, General Chemistry
Abstract

Encapsulation is one of the technologies applied for the formulation of biological control agents. The function of the encapsulating matrix is to protect the biological material from environmental factors, while dehydration allows for its viability to be prolonged. An advantage of dehydrated encapsulation formulations is that they can be stored for long periods. However, vegetative cells require low-stress dehydration processes to prevent their loss of viability. Herein we describe the fabrication of a dehydrated encapsulate of the Streptomyces CDBB1232 mycelium using sodium alginate with a high concentration of mannuronic acid; sodium alginate was added with YGM medium for mycelium protection purposes. The encapsulation was carried out by extrusion, and its dehydration was carried out in a rotating drum fed with air at room temperature (2–10 L min−1). The drying of the capsules under air flows higher than 4 L min−1 led to viability loss of the mycelium. The viability loss can be decreased up to 13% by covering the alginate capsules with gum arabic. Compared to conventional dehydration processes, air moisture removal can be lengthy, but it is a low-cost method with the potential to be scaled.

Published
2022
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11. Steroidal Molecular Rotors with 1,4-Diethynylphenylene Rotators: Experimental and Theoretical Investigations Toward Seeking Efficient Properties

Author

Marcin Górecki, Andrzej Łapiński, Rosa Santillan, Norberto Farfán, Karolina Olszewska, Tomasz Runka, and Izabella Jastrzebska

Subjects
Circular dichroism, Materials science, 010304 chemical physics, Infrared spectroscopy, Dihedral angle, 010402 general chemistry, 01 natural sciences, Article, 0104 chemical sciences, Surfaces, Coatings and Films, Molecular dynamics, symbols.namesake, 0103 physical sciences, Materials Chemistry, symbols, Physical chemistry, Density functional theory, Physical and Theoretical Chemistry, Spectroscopy, Raman spectroscopy, Conformational isomerism
Abstract

Properly designed molecular rotors with sizable stators and a fast-moving rotator could provide efficient building blocks for amphidynamic crystals. Herein, we report the synthesis of steroidal compounds 1, 2, and 3 and their deuterated analogues 1D, 2D, and 3D envisioned to work as molecular rotors. The obtained compounds were characterized by attenuated total reflection-infrared, Raman, and circular dichroism (CD) spectroscopy measurements. The interpretation of spectra was supported by theoretical calculations using density functional theory methods. The analysis of the most characteristic bands confirmed different molecular dynamics of the rotors investigated. Angle-dependent polarized Raman spectra showed the crystallinity of some samples. Electronic CD (ECD) spectra of compounds 1–3 and their relevant deuterated analogues 1D–3D are identical. The increase of the band intensity with lowering the temperature shows that the equilibrium is shifted to the thermodynamically most stable conformer. ECD spectra simulated at the TDFFT level of theory for compound 3 were compared with experimental results. It was proved that conformer 3a, with a torsion angle of +50°, exhibits the best agreement with the experimental results. Simulated vibrational CD and IR spectra for conformer 3a and its deuterated analogue 3Da also display good agreement with experimental results. In light of our comprehensive investigations, we evidenced that steroidal compounds 1, 2, and 3 can work as molecular rotors.

Published
2020

12. Biological Activity of Phytochemicals from Agricultural Wastes and Weeds on Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae)

Author

Analleli Jiménez-Durán, Josefina Barrera-Cortés, Laura Patricia Lina-García, Rosa Santillan, Ramón Marcos Soto-Hernández, Ana C. Ramos-Valdivia, Teresa Ponce-Noyola, and Elvira Ríos-Leal

Subjects
fertility, Environmental effects of industries and plants, Renewable Energy, Sustainability and the Environment, Geography, Planning and Development, fungi, TJ807-830, biocontrol, Meliaceae, phytochemicals, phytolarvicide, Piperaceae, Management, Monitoring, Policy and Law, TD194-195, Renewable energy sources, Environmental sciences, GE1-350
Abstract

Spodoptera frugiperda J.E. Smith (Lepidoptera: Noctuidae) is a polyphagous insect pest native to America. Due to its capacity for adaptation and migration, it is currently located in Africa, Asia, and Oceania, where it threatens agricultural crops. The ability of S. frugiperda to develop resistance to insecticides is one of the reasons for the continuous search for more effective, low-cost, and environmentally friendly control products. In the present work, the insecticidal activity of ethanolic and hexane extracts obtained from fresh and dehydrated leaves of Piper auritum Kunth (Piperales: Piperaceae), Piper umbellatum L. (Piperales: Piperaceae), and Cedrela odorata L. (Sapindales: Meliaceae) was studied against first instar larvae of S. frugiperda. The ethanolic extracts of the dehydrated leaves of C. odorata and P. auritum presented insecticidal activity as high (100% mortality at a concentration of 92 mg/cm2) as that obtained with the positive control, Melia azedarach L. (Sapindales: Meliaceae). The GC-MS analysis of the extracts revealed the presence of phytochemicals classified mainly into the groups of monoterpenes, sesquiterpenes, diterpenes, phenylpropanoids, alcohols, and fatty acids. P. auritum grows and propagates rapidly. In addition, due to its low toxicity in mammals and non-target insects, it is a plant with the potential to be used as a botanical insecticide. The exposure of S. frugiperda larvae to low concentrations of ethanolic extract of P. auritum allowed us to observe their biological activity in the development of this insect. The LC50 was 22.1 mg/cm2. At sublethal concentrations (LC21 and LC35) the low fertility of the emerging adults was noticeable.

Published
2021
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13. Two‐Photon Absorption Properties in 'Push‐Pull' Ruthenium Nitrosyl Complexes with various Fluorenylterpyridine‐Based Ligands

Author

Valerii Bukhanko, Norberto Farfán, Marine Tassé, Rodrigo M. Barba-Barba, Gabriel Ramos-Ortiz, Isabelle Malfant, Rosa Santillan, Pascal G. Lacroix, Andrés Felipe León-Rojas, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Instituto de Quı́mica, Universidad Nacional Autónoma de México, Universidad Nacional Autónoma de México (UNAM), Centro de Investigaciones en Optica (CIO), Consejo Nacional de Ciencia y Tecnología [Mexico] (CONACYT), and Centro de Investigacion y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV)

Subjects
010405 organic chemistry, Chemistry, Photochemistry, chemistry.chemical_element, Ruthenium nitrosyl, Ligands design, 010402 general chemistry, 01 natural sciences, Two-photon absorption, 3. Good health, 0104 chemical sciences, Ruthenium, Inorganic Chemistry, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Push pull
Abstract

International audience; Using the compound [RuII(FT)(bipy)(NO)](PF6)3 (FT is the electron‐rich 4’‐(2‐fluorenyl)‐2,2’:6’,2’’‐terpyridine ligand and bipy is 2–2’bipyridine) as a reference, two new compounds are presented in which carbon‐carbon double and triple bonds are inserted between the fluorenyl substituent and the terpyridine to provide an extended conjugation path. The electronic properties of the three complexes are compared experimentally by UV‐visible spectroscopy and computationally by means of the density functional theory. All of them exhibit a capability for NO release under irradiation on their low‐energy transition located in the 400–500 nm range, with a quantum yield around 0.01. Their two‐photon absorption (TPA) cross sections are investigated by the Z‐scan technique at λ=800 nm. While the reference compound exhibits a cross‐section equal to 108 GM, the introduction of double and triple bonds leads to increased cross‐sections equal to 131 GM and 150 GM, respectively. These values are discussed in reference to the two‐level model in use for “push‐pull” dipolar TPA chromophores.

Published
2021
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14. Synthesis and optical properties of 1-ethyl-indol-3-yl-substituted aza-BODIPY dyes at the 1,7-positions

Author

Luis Loaeza, Valérie Maraval, Norberto Farfán, Geraldyne Castro, Ricardo Corona-Sánchez, Rosa Santillan, Margarita Romero-Ávila, Remi Chauvin, Facultad de Quimica, Universidad Nacional Autonoma de Mexico, Laboratoire de chimie de coordination (LCC), 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)-Centre National de la Recherche Scientifique (CNRS), Departemento de Quimica, Universidad Autonoma Metropolitana-Iztapalapa, Centro de Investigacion y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), CONACYT grant (576732), CONACYT, PAIP, PAPIIT (IN 222819), French-Mexican International Laboratory (LIA-LCMMC-CONACYT) programs, Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Indol-3-yl substituents, Chloroform, Absorption spectroscopy, 010405 organic chemistry, Band gap, Organic Chemistry, Aza-BODIPY, 010402 general chemistry, Photochemistry, 01 natural sciences, Biochemistry, 0104 chemical sciences, Organic semiconductor, chemistry.chemical_compound, Near-infrared, chemistry, Extinction (optical mineralogy), Drug Discovery, Bathochromic shift, Aza-bodipy, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Absorption (chemistry)
Abstract

International audience; New aza-BODIPYs with significant bathochromic shifts in their UV–vis absorption spectrum were synthesized by the installation of 1-ethyl-indol-3-yl moieties at the 1,7-positions of the aza-BODIPY core bearing 4-substituted phenyl or thien-2-yl groups at the 3,5-positions. The compounds described herein show strong NIR absorptions up to 779 nm, and emissions up to 805 nm in chloroform solution, and present large molar extinction coefficients. The absorption and emission bands of aza–BODIPYs were significantly red-shifted, by ca 100 nm, relative to the 3,5-dianisyl-1,7-diphenyl aza-BODIPY. TD-DFT calculations indicate an effective electronic conjugation between the aza-BODIPY core and the substituents. Absorption of the studied aza-BODIPY derivatives corresponds to a charge transfer from donor substituents toward the boron-centered core. Moreover, computational results show that all the compounds present HOMO–LUMO band gap values that are in the organic semiconductor range.

Published
2021
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15. Physicochemical and computational insight of 19 F NMR and emission properties of meso -( o -aryl)-BODIPYs

Author

Armando Ariza, Mónica Farfán-Paredes, Oscar González-Antonio, Rosa Santillan, Norberto Farfán, Pascal G. Lacroix, Diana E. Tahuilan-Anguiano, Jorge Peon, Facultad de Quimica, Universidad Nacional Autonoma de Mexico, Instituto de Quı́mica, Universidad Nacional Autónoma de México, Universidad Nacional Autónoma de México (UNAM), Centro de Investigacion y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Farmácia da Universidade do Porto, Universidad Nacional Autónoma de México = National Autonomous University of Mexico (UNAM), 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)-Centre National de la Recherche Scientifique (CNRS), CONACYT A1-S-7642, PAIP and PAPIIP IN222819, and French-Mexican International Laboratory (LIA-LCMMC-CONACYT FONCYT 069/2018)

Subjects
010405 organic chemistry, Aryl, chemistry.chemical_element, General Chemistry, Fluorine-19 NMR, 010402 general chemistry, 01 natural sciences, Catalysis, Spectral line, 0104 chemical sciences, Rotational energy, Electronegativity, chemistry.chemical_compound, chemistry, Computational chemistry, Materials Chemistry, Fluorine, Molecule, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Quantum
Abstract

International audience; A series of electronic and physicochemical parameters were explored to determine their effect on experimental spectroscopic and photophysical data. Through a systematic obtention of a series of meso-(o-aryl)-BODIPYs, 19F NMR spectra were analyzed and their fluorescence quantum yields in several solvents were measured. Experimental values of 19F chemical shift difference ΔδF correlate well with σ-Hammett constants, which is indicative of the inductive nature of the functional groups on the fluorine atoms. A computational DFT exploration of rotational energy barriers, electrostatic potential maps, group electronegativity, charge partitions and hardness/softness provided insight into how those traits can be directly related to the measured features. Expanded understanding of such characteristics provides design arguments and a structure–property relationship, which in a more advantageous way, would help to understand the properties of the synthesized molecules and of future attempts that are structurally related.

Published
2020
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16. Tuning the Cell Uptake and Subcellular Distribution in BODIPY–Carboranyl Dyads: An Experimental and Theoretical Study

Author

Norberto Farfán, Arturo Jiménez-Sánchez, Ricardo Flores-Cruz, Pablo Labra-Vázquez, Justo Cabrera-González, Pascal G. Lacroix, Cristian Guzmán‐Cedillo, Rosario Núñez, Aylin Galindo‐Hernández, Rosa Santillan, Universidad Nacional Autónoma de México = National Autonomous University of Mexico (UNAM), Laboratoire de chimie de coordination (LCC), 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)-Centre National de la Recherche Scientifique (CNRS), Instituto de Quı́mica, Universidad Nacional Autónoma de México, Institut de Ciència de Materials de Barcelona (ICMAB), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Centro de Investigacion y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), PAPIIT (IN222819), CONACyT (A1-S-7642), Spanish Ministerio de Economia y Competitividad, MICINN (PID2019-106832RB-100), Generalitat de Catalunya (2017/SGR/1720), Universidad Nacional Autónoma de México (UNAM), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Universidad Nacional Autónoma de México, Consejo Nacional de Ciencia y Tecnología (México), Ministerio de Economía y Competitividad (España), and Generalitat de Catalunya

Subjects
Boron Compounds, Fluorophore, Sonogashira coupling, [CHIM.THER]Chemical Sciences/Medicinal Chemistry, Fluorophores, 010402 general chemistry, 01 natural sciences, Catalysis, Imaging, chemistry.chemical_compound, Boron neutron capture therapy, BODIPY, Humans, [CHIM.COOR]Chemical Sciences/Coordination chemistry, 010405 organic chemistry, Organic Chemistry, General Chemistry, Models, Theoretical, Subcellular localization, Fluorescence, 0104 chemical sciences, 3. Good health, Partition coefficient, chemistry, Theranostic, Lipophilicity, BNCT, Biophysics, Carborane, HeLa Cells
Abstract

A set of BODIPY‐carboranyl dyads synthesized by a Sonogashira cross‐coupling reaction, where different C‐substituted ortho‐ and meta‐carboranyl fragments have been linked to a BODIPY fluorophore is described. Chemical, photophysical and physicochemical analyses are presented, including NMR and SXRD experiments, optical absorption/emission studies and log P measurements. These studies, supported by DFT computations (M06‐2X/6‐31G**) provide an explanation to the largely divergent cell income that these fluorescent carboranyl‐based fluorophores display, for which a structural or physicochemical explanation remains elusive. By studying the cell uptake efficiency and subcellular localization for our set of dyads on living HeLa cells, we tracked the origins of these differences to significant variations in their static dipole moments and partition coefficients, which tune their ability to interact with lipophilic microenvironments in cells. Remarkably, m‐carboranyl‐BODIPY derivatives with a higher lipophilicity are much better internalised by cells than their homologous with o‐carborane, suggesting that m‐isomers are potentially better theranostic agents for in vitro bioimaging and boron carriers for BNCT., The work has been performed within the framework of the French-Mexican International Laboratory (LIA-LCMMC). Authors acknowledge support from PAPIIT (IN222819) and CONACyT. The work was supported by Spanish Ministerio de Economía y Competitividad, MINECO (CTQ2016-75150-R) and Generalitat de Catalunya (2017/SGR/1720). Doctoral scholarships were granted by CONACyT to P.L.-V (337958) and R. F.-C. (576635). We thank María E. Ochoa (CINVESTAV-IPN), Marco A. Leyva (CINVESTAV-IPN) and Flor R. Vega (FQ-UNAM) for NMR/HRMS experiments, SXRD experiments and technical support, correspondingly.

Published
2020
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17. State of the Art of Boron and Tin Complexes in Second- and Third-Order Nonlinear Optics §

Author

Pascal G. Lacroix, Alejandro Enriquez‐Cabrera, Cristina C. Jiménez, Norberto Farfán, Javier Ordóñez-Hernández, Oscar González-Antonio, Rosa Santillan, Pablo Labra-Vázquez, Facultad de Quimica, Universidad Nacional Autonoma de Mexico, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Centro de Investigacion y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV)

Subjects
Materials science, Nonlinear optics, Second-Harmonic Generation, chemistry.chemical_element, Organotin complex, 010402 general chemistry, 01 natural sciences, Two-photon absorption, Inorganic Chemistry, lcsh:Inorganic chemistry, Molecule, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Boron, Topology (chemistry), Organoboron complex, 010405 organic chemistry, business.industry, Second-harmonic generation, Chromophore, lcsh:QD146-197, 0104 chemical sciences, chemistry, Optoelectronics, Tin, business
Abstract

International audience; Boron and tin complexes have been a versatile and very interesting scaffold for the design of nonlinear optical (NLO) chromophores. In this paper we present a wide range of reports since the 1990s to date, which include second-order (e.g., second harmonic generation) and third-order (e.g., two-photon absorption) NLO properties. After a short introduction on the origin of the NLO response in molecules, the different features associated with the introduction of these inorganic motifs in the organic-based NLO materials are discussed: Their effect on the accepting/donating capabilities of the substituents, on the efficiency of the _-conjugated linkage, and on the topology of the chromophores which can be tuned from the first generation of “push-pull” chromophores to more sophisticated two- or three-dimensional architectures.

Published
2018
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18. Centrosymmetric Binuclear Boron Compounds Derived from Dithiooxamides: Synthesis, Characterization, and Their Photophysical Properties

Author

Blanca M. Muñoz-Flores, Noemí Waksman, Jesús Lara Cerón, Marisol Ibarra-Rodríguez, Víctor M. Jiménez-Pérez, María E. Ochoa, and Rosa Santillan

Subjects
Diffraction, Article Subject, 010405 organic chemistry, chemistry.chemical_element, General Chemistry, Crystal structure, 010402 general chemistry, 01 natural sciences, Fluorescence, Oxygen, Fluorescence spectroscopy, 0104 chemical sciences, Characterization (materials science), lcsh:Chemistry, Crystallography, lcsh:QD1-999, chemistry, Luminescence, Boron
Abstract

In this paper, we report the synthesis and characterization of new boron compounds derived from dithiooxamides. The compounds were characterized by NMR (1H and 13C), UV-vis, fluorescence spectroscopy, and high resolution mass spectrometry. The crystal structure of the mononuclear boron compound was determined by single-crystal X-ray diffraction analysis. The photophysical properties of the boron compounds were investigated, and we found moderate fluorescence emission (compound 2 ΦF: 4.07% and compound 4 ΦF: 2.89%). We also observed that the mononuclear complex presented greater stability. Compound 4 showed interesting luminescent properties; in solid state, it exhibited an increase in fluorescence by mechanostimuli by changing to a bright red color, and also in solution, it showed a decrease in fluorescence intensity when oxygen and air were supplied to the solution.

Published
2018
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19. ß-Alkoxy-α,ß-unsaturated ketone systems in steroidal frameworks, and their conversion to 23,24- bisnorcholane lactones

Author

Norberto Farfán, Socorro Meza-Reyes, María A. Fernández-Herrera, Roxana Martínez-Pascual, Sara Montiel-Smith, Susana Rincón, Omar Viñas-Bravo, Jesús Sandoval-Ramírez, José Luis Vega-Baez, Rosa E. del Río, Penélope Merino-Montiel, Rosa Santillan, and Guadalupe Hernández-Linares

Subjects
chemistry.chemical_classification, Steric effects, Ketone, Chemistry, Organic Chemistry, Sapogenin, Cleavage (embryo), lcsh:QD241-441, chemistry.chemical_compound, lcsh:Organic chemistry, Unsaturated ketone, Side chain, Alkoxy group, Organic chemistry, Methyl group
Abstract

The cleavage of the spiroketal side chain in 25R and 25S sapogenins by Ac2O/BF3·OEt2, at room temperature, afforded compounds containing a β-alkoxy-α,β-unsaturated ketone system in their steroidal side chains. However, in (25R)-sapogenins, the ring E is cleaved regioselectively while the (25S)-sapogenin affords a mixture of products due to steric hindrance of the methyl group at C-25. The 23-acetyl-22,26-epoxycholest-22-enes (2, and 6) were transformed into the 23-acetyl sapogenins (12, and 13) under basic treatment. These 23-acetyl derivatives are useful intermediates for the preparation of 23,24-bisnorcholane lactones 10, and 11, in high yields.

Published
2005

21. Substituent effects on solvent-free epoxidation catalyzed by dioxomolybdenum(VI) complexes supported by ONO Schiff base ligands

Author

Rosa Santillan, Dominique Agustin, Jean-Claude Daran, Weili Wang, Norberto Farfán, Tomás Alonso Guerrero, Héctor García-Ortega, Rinaldo Poli, Saul R. Merecias, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), IUT 'A' - Département de Chimie [Castres], Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut Universitaire de Technologie - Paul Sabatier (IUT Paul Sabatier), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Universidad Nacional Autónoma de México (UNAM), Centro de Investigacion y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), Institut Universitaire de France (IUF), Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.), 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)-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut Universitaire de Technologie - Paul Sabatier (IUT Paul Sabatier), Université de Toulouse (UT)-Université de Toulouse (UT), and Universidad Nacional Autónoma de México = National Autonomous University of Mexico (UNAM)

Subjects
Molybdenum, Schiff base, Solvent free, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Substituent, chemistry.chemical_element, Tridentate Schiff-base ligands, Epoxidation, [CHIM.CATA]Chemical Sciences/Catalysis, Organic solvent free, Medicinal chemistry, Acceptor, Catalysis, Inorganic Chemistry, chemistry.chemical_compound, chemistry, Materials Chemistry, Nitro, Organic chemistry, Organic solvent-free, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Physical and Theoretical Chemistry
Abstract

International audience; Molybdenum complexes of type [MoO2L](n) (L = tridentate ONO Schiff base ligands based on the salicylidene-2-aminophenolato structure) have been synthesized and used as catalysts for the solvent-free epoxidation of olefins. The effect of donor (diethylamino) and/or acceptor (nitro) substituents has been studied.

Published
2015
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22. Molecular Disorder in (‒)-Encecanescin

Author

Rosa Santillan, Jesús Arrieta, Holber Zuleta-Prada, Lino Reyes, Benito Reyes-Trejo, Diana Guerra-Ramírez, and María Elena Sánchez-Mendoza

Subjects
Models, Molecular, encecanescin, Molecular model, FTIR and NMR spectra, Eupatorium, Molecular Conformation, Pharmaceutical Science, Crystal structure, Crystallography, X-Ray, DFT calculations, Energy minimization, Article, Analytical Chemistry, lcsh:QD241-441, lcsh:Organic chemistry, Drug Discovery, Benzopyrans, Physical and Theoretical Chemistry, Spectroscopy, Conformational isomerism, X-ray diffraction, Plant Extracts, Chemistry, Chemical shift, Organic Chemistry, Stereoisomerism, Carbon, Plant Leaves, Crystallography, Chemistry (miscellaneous), Solvents, Quantum Theory, Thermodynamics, Molecular Medicine, Density functional theory, Chloroform, Protons, Monte Carlo Method, Two-dimensional nuclear magnetic resonance spectroscopy
Abstract

(‒)-Encecanescin (1) has been isolated from the leaves of Eupatorium aschembornianum. Two conformers are present in the crystal structure as a result of molecular disorder. The structure of 1 was established by 1H- and 13C-NMR spectroscopy in CDCl3 solution using 2D NMR techniques (gHSQC, gHMBC and NOESY). A Monte Carlo random search using molecular mechanics followed by the geometry optimization of each minimum energy structure using density functional theory (DFT) calculations at the B3LYP/6–31G* level and a Boltzmann analysis of the total energies generated accurate molecular models describing the conformational behavior of 1. The three most stable conformers 2–4 of compound 1 were reoptimized at the B3LYP/6-311++G(d,p) level of theory using CHCl3 as a solvent. Correlations between the experimental 1H- and 13C-NMR chemical shifts (δexp) have been found, and the GIAO/B3LYP/6-311++G(d,p) calculated magnetic isotropic shielding tensors (σcalc) for conformers 2 and 3, δexp = a + b σcalc, are reported. A good linear relationship between the experimental and calculated NMR data has been obtained for protons and carbon atoms.

Published
2014
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23. Synthesis, X-ray diffraction analysis and nonlinear optical properties of hexacoordinated organotin compounds derived from Schiff bases

Author

Norberto Farfán, Violeta Álvarez-Venicio, Keitaro Nakatani, Blanca M. Muñoz-Flores, Rosa Santillan, Mario Rodríguez, Omar G. Morales-Saavedra, Pascal G. Lacroix, Víctor M. Jiménez-Pérez, Christine Lepetit, Universidad Autonoma de Nuevo Leon [Mexique] (UANL), Centro de Investigacion y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), Facultad de Quimica, Universidad Nacional Autonoma de Mexico, Centro de Investigaciones en Optica, Laboratorio de Óptica No Lineal, Centro de Ciencias Aplicadas y Desarrollo Tecnológico [México] (CCADET-UNAM), Universidad Nacional Autónoma de México (UNAM), Laboratoire Culture et Communication (LCC), Avignon Université (AU), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Photophysique et Photochimie Supramoléculaires et Macromoléculaires (PPSM), and École normale supérieure - Cachan (ENS Cachan)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
010405 organic chemistry, Stereochemistry, Chemistry, Ligand, Organic Chemistry, X-ray, chemistry.chemical_element, 010402 general chemistry, Mass spectrometry, 01 natural sciences, Biochemistry, 0104 chemical sciences, Inorganic Chemistry, Crystallography, Elemental analysis, Atom, Octahedral molecular geometry, X-ray crystallography, Materials Chemistry, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Physical and Theoretical Chemistry, Tin
Abstract

International audience; The reaction of N,N-bis(2-hydroxy-4-R-benzylidene)-1,2-phenylendiimine (1 R = OH, 2 R = OMe) with R′2SnO (R′ = Me, n-Bu, Ph) provided six new organotin derivatives: dimethyl-di-n-butyl- and diphenyl[N,N′-bis(3-hydroxysalicylaldehyde)-1,2-phenylenediiminato]tin(IV) (1a), (1b), (1c) as well as dimethyl-di-n-butyl- and diphenyl[N,N′-bis(3-methoxysalicylaldehyde)-1,2-phenylenediiminato]tin(IV), (2a), (2b), (2c), respectively. All compounds were characterized by 1H, 13C and 119Sn-NMR, elemental analysis, UV, IR, and mass spectrometry. Compounds 2a, 2b and 2c were characterized by single-crystal X-ray structure analysis. In the solid state, 2a, 2b, and 2c showed the Schiff bases backbone in a bent arrangement containing a tin atom with distorted octahedral geometry, where the ligand occupies the four equatorial positions and the methyl, n-butyl, or phenyl groups occupy the trans axial positions. The second-order nonlinear optical response of representative organotin compounds 2a–c was estimated by electric field induced second harmonic (EFISH) measurements where interesting βμ values in the promising range of 10–60 × 10−30 esu were evaluated.

Published
2014
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24. Comparative photo-release of nitric oxide from isomers of substituted terpyridinenitrosylruthenium( ii ) complexes: experimental and computational investigations

Author

Joëlle Akl, Patricia Vicendo, Rosa Santillan, Isabelle Malfant, Norberto Farfán, Pascal G. Lacroix, Isabelle Sasaki, Sonia Mallet-Ladeira, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre [2011-2015] (ISTerre [2011-2015]), Université Joseph Fourier - Grenoble 1 (UJF)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-PRES Université de Grenoble-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Interactions moléculaires et réactivité chimique et photochimique (IMRCP), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Departamento de Quimica Organica, Facultad de Quimica, Universidad Nacional Autonoma de Mexico, Departamen to de Quimica, Centro de Investigacio´n y de Estudios Avanzados del IPN, Institut de Chimie de Toulouse (ICT), 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)-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT), Université de Toulouse (UT)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Fédération de Recherche Fluides, Energie, Réacteurs, Matériaux et Transferts (FERMAT), 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)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Universidad Nacional Autónoma de México = National Autonomous University of Mexico (UNAM), Centro de Investigacion y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Chimie de Toulouse (ICT-FR 2599), 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), and Universidad Nacional Autónoma de México (UNAM)

Subjects
Stereochemistry, Ligand, Trans effect, Pyridines, Radical, Photoelectron Spectroscopy, chemistry.chemical_element, Quantum yield, Crystal structure, Carbon-13 NMR, Crystallography, X-Ray, Nitric Oxide, Photochemical Processes, Ruthenium, Inorganic Chemistry, Crystallography, chemistry, X-Ray Diffraction, [CHIM]Chemical Sciences, [CHIM.COOR]Chemical Sciences/Coordination chemistry, HOMO/LUMO, ComputingMilieux_MISCELLANEOUS
Abstract

International audience; The 4[prime or minute]-(2-fluorenyl)-2,2[prime or minute]:6[prime or minute],2[prime or minute][prime or minute]-terpyridine (FT) ligand and its cis(Cl,Cl)- and trans(Cl,Cl)-[RuII(FT)Cl2(NO)](PF6) complexes have been synthesized. Both isomers were separated by HPLC and fully characterized by 1H and 13C NMR. The X-ray diffraction crystal structures were solved for FT (Pna21 space group, a = 34.960(4), b = 5.9306(7), c = 9.5911(10) A), and trans(Cl,Cl)-[RuII(FT)Cl2(NO)](PF6)[middle dot]MeOH (P[1 with combining macron] space group, a = 10.3340(5), b = 13.0961(6), c = 13.2279(6) A, [small alpha] = 72.680(2), [small beta] = 70.488(2), [gamma] = 67.090(2)[degree]). Photo-release of NO[radical dot] radicals occurs under irradiation at 405 nm, with a quantum yield of 0.31 and 0.10 for cis(Cl,Cl)-[RuII(FT)Cl2(NO)](PF6) and trans(Cl,Cl)-[RuII(FT)Cl2(NO)](PF6), respectively. This significant difference is likely due to the trans effect of Cl-, which favors the photo-release. UV-visible spectroscopy and cyclic voltammetry indicate the formation of ruthenium(iii) species as photoproducts. A density functional theory (DFT) analysis provides a rationale for the understanding of the photo-physical properties, and allows relating the weakening of the Ru-NO bond, and finally the photo-dissociation, to HOMO [rightward arrow] LUMO excitations.

Published
2014
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25. The amide bridge in donor-acceptor systems: delocalization depends on push-pull stress

Author

Isabelle Malfant, Rosa Santillan, Mauricio Maldonado-Domínguez, Margarita Romero, Norberto Farfán, Pascal G. Lacroix, Blas Flores-Pérez, Rafael Arcos-Ramos, Universidad Nacional Autónoma de México (UNAM), Facultad de Quimica, Universidad Nacional Autonoma de Mexico, Centro de Investigacion y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées

Subjects
010405 organic chemistry, Chemistry, Solvatochromism, Nonlinear optics, General Chemistry, Electron, 010402 general chemistry, 01 natural sciences, Catalysis, 0104 chemical sciences, Delocalized electron, chemistry.chemical_compound, Computational chemistry, Intramolecular force, Amide, Materials Chemistry, Molecule, Molecular orbital, [CHIM.COOR]Chemical Sciences/Coordination chemistry
Abstract

International audience; Transmission of electronic information through amide bonds may be, under appropriate conditions, effectively achieved. In this work, a family of explicitly designed donor-(amide bridge)-acceptor architectures was synthesized. NMR studies and UV-vis absorption solvatochromism support that cross-conjugation leads to measurable polarization across push-pull, amide-bridged molecules. Computational analysis of structural parameters and frontier molecular orbitals shows the contribution of an additional, dienoid amide canonical structure to intramolecular electron delocalization, as the electron donor-acceptor strength of the substituents increases. Within the context of nonlinear optics and molecular materials, computational comparison between amide-bridged molecules and those containing typical linkers shows that there is a compromise between nonlinear optical response, ease of synthesis and chemical inertness, making the systems studied herein interesting alternatives for such applications.

Published
2014
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26. 4-[(E)-(4-Fluorobenzylidene)amino]benzoic acid

Author

Víctor M. Jiménez Pérez, Maria Eugenia Ochoa, Noemí Waksman, Blanca M. Muñoz-Flores, and Rosa Santillan

Subjects
Crystallography, Hydrogen bond, General Chemistry, Dihedral angle, Condensed Matter Physics, Bioinformatics, Organic Papers, Medicinal chemistry, Crystal, chemistry.chemical_compound, chemistry, QD901-999, Physics::Atomic and Molecular Clusters, Molecule, Condensed Matter::Strongly Correlated Electrons, General Materials Science, Physics::Chemical Physics, Benzene, Benzoic acid
Abstract

In the title compound, C14H10FNO2, the benzene rings make a dihedral angle of 57.50 (13)°, and the molecule has an E configuration about the C=N bond. In the crystal, molecules are linked via pairs of O—H...O hydrogen bonds, forming inversion dimers.

Published
2012

27. Synthesis and fluorescence emission of neutral and anionic di- and tetra-carboranyl compounds

Author

Albert Ferrer-Ugalde, Elba Xochitiotzi, Norberto Farfán, Reijo Sillanpää, Arturo Abreu, Francesc Teixidor, Rosa Santillan, Frédéric Lerouge, Rosario Núñez, Clara Viñas, Laboratoire de Chimie - UMR5182 (LC), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon)-Institut de Chimie du CNRS (INC), Institut de Ciència de Materials de Barcelona (ICMAB), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), University of Jyväskylä (JYU), Universidad Nacional Autónoma de México (UNAM), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Universidad Nacional Autónoma de México = National Autonomous University of Mexico (UNAM)

Subjects
Boron Compounds, Models, Molecular, Magnetic Resonance Spectroscopy, Substituent, Salt (chemistry), Ether, 010402 general chemistry, Photochemistry, Crystallography, X-Ray, 01 natural sciences, Inorganic Chemistry, chemistry.chemical_compound, Polymer chemistry, Pyridine, Molecule, ta116, Tetramethylammonium, chemistry.chemical_classification, Luminescent Agents, 010405 organic chemistry, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Aryl, [CHIM.MATE]Chemical Sciences/Material chemistry, 0104 chemical sciences, Spectrometry, Fluorescence, chemistry, Carborane
Abstract

A new family of photoluminescent neutral and anionic di-carboranyl and tetra-carboranyl derivatives have been synthesized and characterized. The reaction of α,α'-bis(3,5-bis(bromomethyl)phenoxy-m-xylene with 4 equiv. of the monolithium salt of 1-Ph-1,2-C(2)B(10)H(11) or 1-Me-1,2-C(2)B(10)H(11) gives the neutral tetracarboranyl-functionalized aryl ether derivatives closo-1 and closo-2, respectively. The addition of the monolithium salt of 1-Ph-1,2-closo-C(2)B(10)H(11) to α,α,'-dibromo-m-xylene or 2,6-dibromomethyl-pyridine gives the corresponding di-carboranyl derivatives closo-3 and closo-4. These compounds, which contain four or two closo clusters, were degraded using the classical method, KOH in EtOH, affording the corresponding nido species, which were isolated as potassium or tetramethylammonium salts. All the compounds were characterized by IR, (1)H, (11)B and (13)C NMR spectroscopy, and the crystal structure of closo-3 was analysed by X-ray diffraction. The carboranyl fragments are bonded through CH(2) units to different organic moieties, and their influence on the photoluminescent properties of the final molecules has been studied. All the closo- and nido-carborane derivatives exhibit a blue emission under ultraviolet excitation at room temperature in different solvents. The fluorescence properties of these closo and nido-derivatives depend on the substituent (Ph or Me) bonded to the C(cluster), the solvent polarity, and the organic unit bearing the carborane clusters (benzene or pyridine). In the case of nido-derivatives, an important effect of the cation is also observed.

Published
2011
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28. Synthesis, characterization and nonlinear optical (NLO) properties of a push-pull bisboronate chromophore with a potential electric field induced NLO switch

Author

Norberto Farfán, Jean François Lamère, Rosa Santillan, José María Rivera, Pascal G. Lacroix, Keitaro Nakatani, Laboratoire de chimie de coordination ( LCC ), Centre National de la Recherche Scientifique ( CNRS ), Departamento de Quimica Organica, Facultad de Quimica, Universidad Nacional Autonoma de Mexico, Departamen to de Quimica, Centro de Investigacio´n y de Estudios Avanzados del IPN, Laboratoire de Photophysique et Photochimie Supramoléculaires et Macromoléculaires ( PPSM ), École normale supérieure - Cachan ( ENS Cachan ) -Centre National de la Recherche Scientifique ( CNRS ), Institut d'Alembert ( IDA ), Centre National de la Recherche Scientifique ( CNRS ) -École normale supérieure - Cachan ( ENS Cachan ), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Photophysique et Photochimie Supramoléculaires et Macromoléculaires (PPSM), École normale supérieure - Cachan (ENS Cachan)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut d'Alembert (IDA), and École normale supérieure - Cachan (ENS Cachan)-Centre National de la Recherche Scientifique (CNRS)

Subjects
organometallic chemistry, ab-initio, Field (physics), Hyperpolarizability, rotary motion, 02 engineering and technology, 010402 general chemistry, boron-nitrogen, 01 natural sciences, Molecular physics, neutron-capture therapy, Optics, Electric field, arylboronic acids, Materials Chemistry, molecular hyperpolarizabilities, business.industry, Chemistry, Nonlinear optics, General Chemistry, Chromophore, 021001 nanoscience & nanotechnology, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Intramolecular force, [ CHIM.THEO ] Chemical Sciences/Theoretical and/or physical chemistry, Electric potential, 0210 nano-technology, business, Ground state, hyper-rayleigh scattering, crystal-structures, metal-complexes
Abstract

International audience; A new bisboronate with five six-membered ring heterobicycles was prepared by reaction of [2-(2-hydroxy-4-diethylaminobenzylidene)amino]-5-nitroaminophenol and 1,4-phenyldiboronic acid, and its quadratic nonlinear optical (NLO) response was compared to that of a related monoboronate species. A computational investigation conducted within the framework of the DFT theory, at the B3PW91/6-31G* level, indicates that, while the diboronate derivative exhibits a centrosymmetric conformation in the ground state, and hence a vanishing quadratic hyperpolarizability (beta), the application of an external electric field provides a gradual intramolecular rotation of the two "push-pull'' sub-units which reaches 128 degrees for a field intensity of 10(-3) a.u. and leads to a beta value equal to 49.2 x 10(-30) cm(5) esu(-1). This result suggests a possibility for a molecular NLO switch induced by an electric field in such systems. Experimentally, the NLO response measured by the electric field induced second harmonic (EFISH) technique indicates an NLO response (expressed as the mu x beta product) 1.95 times larger for the bisboronate than for the monoboronate analogue, thus suggesting that, although the ground state conformation is centrosymmetric, the "push-pull'' sub-units are in quasi-free rotation at room temperature.

Published
2006
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29. Dimeric Boronates Derived from the Reaction of Schiff Bases and Boronic Acids

Author

Rosa Santillan, Norberto Farfán, and Victor Barba

Subjects
chemistry.chemical_compound, Schiff base, Chemistry, Stereochemistry, macrocyclic chemistry, tridentate ligands, macrocyclic chem, General Chemistry, Química, boron, Medicinal chemistry
Abstract

The one-pot synthesis of dimeric boron complexes is reported. The compounds were obtained by reaction of Schiff bases (tridentate ligands) with trans-beta-phenylvinylboronic acid, 3-thiopheneboronic acid and methylboronic acid. Building of the dimeric structures is favored by the presence of intramolecular N-> B coordination bonds, resulting in the formation of ten-membered ring heterocycles. An X-ray crystallographic analysis for one of them confirmed the dimeric nature of these compounds. A síntese one-pot de complexos diméricos de boro é descrita. Os compostos foram obtidos pela reação de bases de Schiff (ligantes tridentados) com ácido trans-beta-fenilvinilborônico, ácido 3-tiofeninoborônico e ácido metilborônico. A construção das estruturas diméricas é favorecida pela presença de ligações de coordenação N-> B intramoleculares, resultando na formação de anéis heterociclicos de dez membros. A análise cristalográfica de raio X de um deles confirmou a natureza dimérica desses compostos.

Published
2005

30. (25R)-16β-Acet­oxy-3β-bromo-23′,26-ep­oxy-23′,25-dimethyl-5α-cholest-23,23′-en-6-one dichloro­methane monosolvate

Author

Yliana López, Norberto Farfán, Rosa Santillan, R. Yépez, María E. Ochoa, and Susana Rincón

Subjects
Chemistry, Hydrogen bond, General Chemistry, Crystal structure, Condensed Matter Physics, Ring (chemistry), Bioinformatics, Medicinal chemistry, Organic Papers, Methane, Stereocenter, Solvent, Crystal, chemistry.chemical_compound, General Materials Science
Abstract

The crystal structure of the title compound, C31H45BrO5·CH2Cl2, prepared in six steps from diosgenin, confirmed that the configurations of the stereogenic centers, positions 20S and 25R, remain unchanged during the reaction. The six-membered A, B and C rings have chair conformations. The five-membered ring D has an envelope conformation (with the methyl-substituted C atom fused to ring C as the flap) and the six-membered dihydro­pyran ring E adopts a twist-boat conformation. In the crystal, mol­ecules are linked via C—H⋯O and C—H⋯Cl hydrogen bonds, the latter involving the dichloro­methane solvent mol­ecule, forming a three-dimensional supra­molecular network.

Published
2012

32. Nanoemulsified Formulation of Cedrela odorata Essential Oil and Its Larvicidal Effect against Spodoptera frugiperda (J.E. Smith)

Author

Ana Sofía Lemus de la Cruz, Josefina Barrera-Cortés, Laura Patricia Lina-García, Ana C. Ramos-Valdivia, and Rosa Santillán

Subjects
botanicals, fall armyworm, sustainable insecticides, wood waste, Organic chemistry, QD241-441
Abstract

Cedrela odorata L. is a plant species from the Meliaceae family that is cultivated for timber production. Although the C. odorata essential oil (EO) contains mainly sesquiterpenes, its insecticidal potential is unknown. The lipophilic properties and high degradation capacity of EOs have limited their application for use in pest control. However, the currently available knowledge on the nanoemulsification of EOs, in addition to the possibility of improving their dispersion, would allow them to prolong their permanence in the field. The objective of the present work was to develop a nanoemulsion of the C. odorata EO and to evaluate its larvicidal activity against Spodoptera frugiperda. The EO was obtained by the hydrodistillation of C. odorata dehydrated leaves, and the nanoemulsion was prepared with non-ionic surfactants (Tween 80 and Span 80) using a combined method of agitation and dispersion with ultrasound. The stability of the nanoemulsion with a droplet diameter of C. odorata EO and its corresponding nanoemulsion presented lethal properties against S. frugiperda. The results obtained provide guidelines for the use of wood waste to produce sustainable and effective insecticides in the fight against S. frugiperda. In addition, considering that a phytochemical complex mixture allows the simultaneous activation of different action mechanisms, the development of resistance in insects is slower.

Published
2022
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33. Synthesis and fluorescence emission of neutral and anionic di- and tetra-carboranyl compoundsCCDC reference number 802843. For crystallographic data in CIF or other electronic format see DOI: 10.1039/c1dt10309a.

Author

Frédéric Lerouge, Albert Ferrer-Ugalde, Clara Viñas, Francesc Teixidor, Reijo Sillanpää, Arturo Abreu, Elba Xochitiotzi, Norberto Farfán, Rosa Santillan, and Rosario Núñez

Subjects
PHOTOLUMINESCENCE, NUCLEAR magnetic resonance spectroscopy, X-ray diffraction, SOLVENTS, CARBORANES, CHEMICAL structure, ADDITION reactions
Abstract

A new family of photoluminescent neutral and anionic di-carboranyl and tetra-carboranyl derivatives have been synthesized and characterized. The reaction of α,α′-bis(3,5-bis(bromomethyl)phenoxy-m-xylene with 4 equiv. of the monolithium salt of 1-Ph-1,2-C2B10H11or 1-Me-1,2-C2B10H11gives the neutral tetracarboranyl-functionalized aryl ether derivatives closo-1and closo-2, respectively. The addition of the monolithium salt of 1-Ph-1,2-closo-C2B10H11to α,α,′-dibromo-m-xylene or 2,6-dibromomethyl-pyridine gives the corresponding di-carboranyl derivatives closo-3and closo-4. These compounds, which contain four or two closoclusters, were degraded using the classical method, KOH in EtOH, affording the corresponding nidospecies, which were isolated as potassium or tetramethylammonium salts. All the compounds were characterized by IR, 1H, 11B and 13C NMR spectroscopy, and the crystal structure of closo-3was analysed by X-ray diffraction. The carboranyl fragments are bonded through CH2units to different organic moieties, and their influence on the photoluminescent properties of the final molecules has been studied. All the closo- and nido-carborane derivatives exhibit a blue emission under ultraviolet excitation at room temperature in different solvents. The fluorescence properties of these closoand nido-derivatives depend on the substituent (Ph or Me) bonded to the Ccluster, the solvent polarity, and the organic unit bearing the carborane clusters (benzene or pyridine). In the case of nido-derivatives, an important effect of the cation is also observed. [ABSTRACT FROM AUTHOR]

Published
2011
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34. X-Ray crystallographic and spectroscopic properties of eight Schiff bases as evidence of the proton transfer reaction. Role of the intermolecular hydrogen bondElectronic supplementary information (ESI) available: NMR characterization and experimental procedures for the preparation of all compounds, figure with high temperature VT NMR data of compound 5in DMSO-d6, table with a complete list of intra- and intermolecular contacts, additional figure for the crystal packing of compound 7. CCDC reference numbers 712147(1), 712151(2), 712153(3), 712149(4) 712150(5), 712154(6), 712155(7) and 712152(8). For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c0nj00179a

Author

Oscar Domínguez, Braulio Rodríguez-Molina, Mario Rodríguez, Armando Ariza, Norberto Farfán, and Rosa Santillan

Subjects
X-ray crystallography, SCHIFF bases, PROTON transfer reactions, HYDROGEN bonding, NUCLEAR magnetic resonance spectroscopy, MOLECULAR structure, TAUTOMERISM, POLYCRYSTALS, SOLID state chemistry
Abstract

A spectroscopic study of several ortho-hydroxy Schiff bases was carried out, and the corresponding crystal structures were analyzed in order to identify their characteristic hydrogen bonding patterns. The X-ray analysis showed that the enol (O–HN) tautomer is the most stable in compounds 1–3whereas the keto (N–HO) form is preferred in compounds 4–7. The specific intermolecular O–HO hydrogen bonding interactions that control the supramolecular arrangement of each tautomer are discussed. Additionally, a complete characterization of the polycrystalline samples was attained using solid-state NMR and IR experiments. Solution VT NMR and UV-visible experiments were also used to obtain valuable insights about the nature and stability of the tautomers. [ABSTRACT FROM AUTHOR]

Published
2011

35. Synthesis and non-linear optical characterization of novel borinate derivatives of cinnamaldehydeElectronic supplementary information (ESI) available: Cartesian coordinates for calculated structures of 1a–1cand 2a–2c. CCDC reference number 705151. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/b820435g

Author

Mario Rodríguez, José Luis Maldonado, Gabriel Ramos-Ortíz, Jean François Lamère, Pascal G. Lacroix, Norberto Farfán, Ma. Eugenia Ochoa, Rosa Santillan, Marco Antonio Meneses-Nava, Oracio Barbosa-García, and Keitaro Nakatani

Subjects
ALDEHYDES, ORGANIC synthesis, CHEMICAL structure, IMINES, LIGANDS (Chemistry), NUCLEAR magnetic resonance spectroscopy, ELECTRON donor-acceptor complexes, NONLINEAR optics
Abstract

Herein is reported the synthesis of three new borinates (2a–2c) derived from bidentate imine ligands (1a–1c), which were prepared from the corresponding cinnamaldehyde derivatives. All compounds were characterized by MS, IR and NMR spectroscopy. The nonlinear optical (NLO) characterization of these molecules having push–pull properties is included. Second order nonlinearities were evaluated at 1.907 μm by the electric-field-induced second harmonic (EFISH) technique through the β×μproduct, showing a trend for a general increase of the NLO response after boron complexation. For borinate 2c, which has strong electron-donating and electron-withdrawing groups at opposite ends of the π-backbone, βμ= 1560 × 10−30D cm5esu−1, showing a three-fold increase with respect to the ligand 1c(βμ= 542 × 10−30D cm5esu−1). Third-order nonlinearities, in solid films, were evaluated employing the third harmonic generation (THG) Maker Fringe technique showing χ(3)susceptibilities of the order of χ(3)∼10−12esu at the infrared wavelength of 1.2 μm. Compounds with the highest χ(3)values correspond to those having the largest βμproduct: for 1cχ(3)= 1.1 × 10−11esu and for 2cχ(3)= 8.4 × 10−12esu. [ABSTRACT FROM AUTHOR]

Published
2009

36. High boron content carboranyl-functionalized aryl ether derivatives displaying photoluminescent properties.

Author

Frédéric Lerouge, Clara Viñas, Francesc Teixidor, Rosario Núñez, Arturo Abreu, Elba Xochitiotzi, Rosa Santillan, and Norberto Farfán

Subjects
BORON, NONMETALS, ORGANIC compounds, SPECTRUM analysis
Abstract

The reaction of α,α′-bis(3,5-bis(bromomethyl)phenoxy-p-xylene (3) with 4 equiv of the monolithium salt of 1-Ph-1,2-C2B10H11 or 1-Me-1,2-C2B10H11 gave the corresponding neutral carboranyl-functionalized aryl ether derivatives closo-4 and closo-5, respectively. These compounds contain four closo clusters that were degraded using basic conditions with KOH in EtOH, affording the corresponding nido-6 and nido-7 as potassium salts. Nido species were also isolated with tetramethylammonium as cation giving compounds nido-8 and nido-9 in good yield. The potassium salts showed good solubility in water and polar solvents. All these compounds were characterized by 1H, 11B and 13C NMR spectroscopy and UV-vis. The electronic data in different solvents indicated a solvatochromic shift for all compounds and a red shift of the absorption maxima for the nido species with respect to the closo derivatives. These neutral and anionic carboranyl-functionalized aryl ether derivatives represent a new family of high boron content luminescent compounds that show strong fluorescence emission in different solvents at room temperature. This phenomenon is very interesting considering the fact that none of the precursors have such a property. The fluorescence emission depends on the cluster substituent (Ph or Me) and the solvent polarity. Additionally, the fluorescence emission intensity was clearly dependent on the solvent polarity; the closo species showed strongest fluorescence intensities in the non-polar solvents, while anionic species were highly emissive in polar solvents. [ABSTRACT FROM AUTHOR]

Published
2007
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39. Pseudo-Four Component Synthesis of Mono- and Di-Benzylated-1,2,3-Triazoles Derived from Aniline

Author

Daniel Mendoza-Espinosa, Guillermo E. Negron-Silva, Leticia Lomas-Romero, Atilano Gutierrez-Carrillo, and Rosa Santillán

Subjects
click chemistry, aniline, dibenzylated triazoles, catalysis, Organic chemistry, QD241-441
Abstract

The pseudo-four component click synthesis of dibenzylated 1,2,3-triazoles derived from aniline is reported. The cycloaddition of sodium azide to N-(prop-2-ynyl)-benzenamine (I) in the presence of equimolar amounts of p-substituted benzyl derivatives, yields a mixture of mono- and dibenzylated 1,2,3-triazoles. When two equivalents of the benzyl derivative are added to the multicomponent reaction, the selective preparation of the dibenzylated compounds is achieved. The reactivity of the aniline N-H bond in monobenzylated 1,2,3-triazoles was tested by treatment with one equivalent of a p-substituted benzyl chloride at 40 °C, rendering the dibenzylated derivatives quantitatively.

Published
2013
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41. Hallazgo de Panstrongylus rufotuberculatus (Champion, 1899) (Hemiptera, Reduviidae, Triatominae) en ambiente domiciliario en la Región Piura, Perú Intra-domiciliary capture of Panstrongylus rufotuberculatus (Champion, 1899) (Hemiptera, Reduviidae, Triatominae) in Piura, Peru

Author

Edgard Marín, Rosa Santillán, César Cuba, José Jurberg, and Cleber Galvão

Subjects
Panstrongylus, Control Vectorial, Entomología, Vector Control, Entomology, Medicine, Public aspects of medicine, RA1-1270
Abstract

Panstrongylus rufotuberculatus presenta una amplia distribución en América Central y del Sur con un comportamiento de especie silvestre. En el Perú ha sido registrado en Tumbes, Piura y Cuzco, siendo descrito en casas de localidades de este último departamento. En el presente trabajo se documenta evidencia de domiciliación de P. rufotuberculatus en la localidad de Chirinos-La Pareja, Distrito de Suyo, Provincia de Ayabaca, Región Piura, Perú (4º46'S, 79º93'W). Se capturaron 28 especímenes: 3 ninfas II, 4 ninfas III, 2 ninfas IV, 8 ninfas V, 3 machos y 8 hembras, lo que evidencia la existencia de una colonia intradomiciliar en "cuyeros" (criaderos de Cavia porcellus) camas y paredes del dormitorio de la vivienda. Exámenes parasitológicos de heces evacuadas espontáneamente fueron negativos a infección natural por Trypanosoma cruzi. A pesar de que se ha reportado la presencia de P. rufotuberculatus en localidades de Tumbes y Piura, es la primera vez que se documenta su tendencia sinantrópica en la Región. La importancia de esta especie y posteriores investigaciones permitirán evaluar su etología y potencial vectorial de trypanosomiasis americana. Se recomienda una cuidadosa actividad de vigilancia entomo-epidemiológica para esta especie y las otras que coexisten simpátricamente, actualmente en esta región del norte de Perú.Panstrongylus rufotuberculatus is widely distributed in Central and South America. In Peru, it has been found in Tumbes, Piura, and Cuzco. The authors report the presence of P. rufotuberculatus in Chirinos-La Pareja, Suyo district, Ayabaca Province, Piura Region, Peru. Twenty-eight specimens were collected in two of 15 dwellings: three 2nd instar, four 3rd instar, two 4th instar, and eight 5th instar nymphs, three male and eight female, in an intra-domiciliary colony of guinea pigs (Cavia porcellus, raised indoors as a source of diet protein) and beds and bedroom walls. None of the fecal samples were naturally infected with Trypanosoma cruzi. This is the first report of synanthropic presence of P. rufotuberculatus in the region. The finding emphasizes the need for careful entomological and epidemiological surveillance of this and other triatomine species in the Region.

Published
2007
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42. Zinc Deficiency in Calcareous Soils: A Bibliometric Analysis from 1989 to 2024

Author

Osbaldo Martínez-Ríos, Ángel Bravo-Vinaja, Cesar San-Martín-Hernández, Claudia Isabel Hidalgo-Moreno, Marco Antonio Sánchez-de-Jesús, Joseph David Llampallas-Díaz, Diana Rosa Santillan-Balderas, and José Concepción García-Preciado

Subjects
crops, calcium carbonates, bibliometric indicators, research topics, VOSviewer, Agriculture (General), S1-972
Abstract

Zinc (Zn) deficiency in crops is a global issue, particularly in plants grown in calcareous soils, where Zn is often adsorbed or precipitated by calcium carbonates. The aim of this study was to identify and quantify, through bibliometric analysis, the scientific production related to Zn deficiency in calcareous soils over the last 36 years (1989–2024). A total of 374 documents were retrieved through a search on the Web of Science (WOS) platform, specifically in the Science Citation Index Expanded (SCIE) and Social Science Citation Index (SSCI) databases. Of these, only 198 articles were directly relevant to the topic and were used for the analysis. Unidimensional and multidimensional bibliometric indicators were evaluated using Excel and VOSviewer software. The results confirm that the number of articles has increased in recent years. The most influential authors, journals, articles, institutions, and countries in this research area were identified. In addition, collaboration networks between authors and countries, as well as the predominant research topics, were determined. This study provides a comprehensive overview of this field on a global scale and serves as a useful reference for scientists interested in conducting future research on related topics.

Published
2024
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44. Los beneficios tributarios como mecanismos para incentivar la donación de alimentos en supermercados en el área metropolitana de Lima, Perú

Author

Stefany Fabiola Lozano Requelme, Martha Rosa Santillan Valderrama, and Kelly del Rosario Yactayo Melo

Subjects
tributación, donación de alimentos, objetivos de desarrollo sostenible, responsabilidad social, beneficios tributarios, Accounting. Bookkeeping, HF5601-5689
Abstract

En Perú, hasta inicios de 2016, los alimentos con fechas próximas de vencimiento, a pesar de que se encontraran en buen estado, no salían a la venta al público ni tampoco eran donados a entidades como bancos de alimentos; esto porque ambas operaciones eran consideradas como operaciones gravadas. En ese sentido, las empresas con el fin de poder recuperar algo del gasto en el que incurrieron en la compra de dichos alimentos debían destruirlos, una medida opuesta a una lógica económica racional, así como al cumplimiento de los Objetivos de Desarrollo Sostenible (ODS). El objetivo de este trabajo fue determinar si los beneficios de la reforma tributaria peruana de 2016 funcionaron de manera eficaz como mecanismo de incentivo para la donación de alimentos en los supermercados que se encuentran en al área metropolitana de Lima, Perú. Para esta investigación se empleó un enfoque mixto, de tipo descriptivo-explicativo a partir de la comparación de marcos normativos, con el cual se buscó clarificar los alcances fiscales y parafiscales de la indicada norma tributaria en el Perú y su impacto en pro del desarrollo social y los efectos que tiene como medida de responsabilidad social.

Published
2018
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