Sylvain Lectard - Academia.edu (original) (raw)
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Papers by Sylvain Lectard
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Pure and Applied Chemistry, 2006
Studies regarding the transition-metal-catalyzed decomposition of nitrogen derivatives toward Cur... more Studies regarding the transition-metal-catalyzed decomposition of nitrogen derivatives toward Curtius rearrangement and the formation of nitrenes which undergo C-H insertion and aziridination reactions are presented. These processes lead to the formation of C-N bond with a high level of selectivity and efficiency.
Organic Letters, 2007
Pyridine copper complexes were found as active catalysts for the intramolecular aziridination of ... more Pyridine copper complexes were found as active catalysts for the intramolecular aziridination of allylic N-tosyloxycarbamates and the intermolecular aziridination of styrenes with trichloroethyl N-tosyloxycarbamates. Free aziridines were easily obtained by basic deprotection of the trichloroethyl group.
Angewandte Chemie International Edition, 2012
Scheme 1. Enantioselective mono-fluorination of a-keto esters. OTf = trifluoromethanesulfonate.
Tetrahedron: Asymmetry, 2010
As a part of our research project on hard anion-late transition metal complexes as mild acid–base... more As a part of our research project on hard anion-late transition metal complexes as mild acid–base catalysts, we describe herein that CuII hydroxo complexes having chiral N-substituted-diaminocyclohexanes are mild and selective catalysts, which are applicable to the catalytic asymmetric conjugate addition of α-keto esters to nitroolefins. The reaction proceeded diastereoselectively without the detectable formation of self-aldol products, affording the corresponding
Journal of the American Chemical Society, 2005
The Japan Society of Applied Physics, 2019
Applied Physics Express
Control of the carrier density with high doping levels is a fundamental technology in semiconduct... more Control of the carrier density with high doping levels is a fundamental technology in semiconductor processing. However, unavoidable structural disorder in organic semiconductors can be introduced by chemical doping methods. Here, we synthesize a novel class of ionic polymers that generate a quasi-permanent electric field, and demonstrate that organic semiconductors in proximity to the ionic polymer can be electrostatically doped with significantly high carrier densities up to 5.6 × 10 13 cm −2 , which results in a low sheet resistance of ca. 60 kΩ. Electret doping presented here is expected to lead to an in-depth understanding of electric phase transitions in organic semiconductors.
![Research paper thumbnail of Naked d-orbital in a centrochiral Ni(II) complex as a catalyst for asymmetric [3+2] cycloaddition](https://attachments.academia-assets.com/70626469/thumbnails/1.jpg)
](Nature Communications
Chiral metal catalysts have been widely applied to asymmetric transformations. However, the elect... more Chiral metal catalysts have been widely applied to asymmetric transformations. However, the electronic structure of the catalyst and how it contributes to the activation of the substrate is seldom investigated. Here, we report an empirical approach for providing insights into the catalytic activation process in the distorted Ni(II)-catalysed asymmetric [3 þ 2] cycloaddition of a-ketoesters. We quantitatively characterize the bonding nature of the catalyst by means of electron density distribution analysis, showing that the distortion around the Ni(II) centre makes the dz 2 orbital partially 'naked', wherein the labile acetate ligand is coordinated with electrostatic interaction. The electron-deficient dz 2 orbital and the acetate act together to deprotonate the a-ketoester, generating the (L)-Ni(II)-enolate. The solid and solution state analyses, together with theoretical calculations, strongly link the electronic structure of the centrochiral octahedral Ni(II) complex and its catalytic activity, depicting a cooperative mechanism of enolate binding and outer sphere hydrogen-bonding activation.
Tetrahedron Letters, Jul 1, 2009
Advanced Synthesis Catalysis, Nov 2, 2010
Since the incorporation of fluorine into biologically active compounds often enhances the propert... more Since the incorporation of fluorine into biologically active compounds often enhances the properties of the parent compounds, there is a considerable demand for efficient enantioselective fluorination reactions. Over the past decade, a range of metal-catalyzed and organocatalyzed fluorination reactions has been developed. Nowadays, fluorine can be catalytically introduced into many compounds in good yield and with high enantioselectivity, and the scope of these reactions is broad. Herein, we review recent progress in the field of catalytic enantioselective fluorination reactions, including their scope and mechanism. 1 Introduction 2 Metal Catalysis 2.1 Fluorination of b-Dicarbonyl Compounds 2.2 Fluorination of b-Ketophosphonates 2.3 a-Fluorination of a-Cyanophosphonates and a-Cyano Esters 2.4 Mechanistic Considerations 2.5 Oxindole Derivatives 2.6 a-Arylacetic Acid Derivatives 3 Organocatalysis 3.
Advanced Synthesis Catalysis, Feb 15, 2011
ABSTRACT An organocatalytic enantioselective aziridination reaction of α,β-unsaturated aldehydes ... more ABSTRACT An organocatalytic enantioselective aziridination reaction of α,β-unsaturated aldehydes including aromatic substrates using N-arenesulfonyloxycarbamates in the presence of diphenylprolinol triethylsilyl ether and sodium carbonate or sodium acetate is described.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Pure and Applied Chemistry, 2006
Studies regarding the transition-metal-catalyzed decomposition of nitrogen derivatives toward Cur... more Studies regarding the transition-metal-catalyzed decomposition of nitrogen derivatives toward Curtius rearrangement and the formation of nitrenes which undergo C-H insertion and aziridination reactions are presented. These processes lead to the formation of C-N bond with a high level of selectivity and efficiency.
Organic Letters, 2007
Pyridine copper complexes were found as active catalysts for the intramolecular aziridination of ... more Pyridine copper complexes were found as active catalysts for the intramolecular aziridination of allylic N-tosyloxycarbamates and the intermolecular aziridination of styrenes with trichloroethyl N-tosyloxycarbamates. Free aziridines were easily obtained by basic deprotection of the trichloroethyl group.
Angewandte Chemie International Edition, 2012
Scheme 1. Enantioselective mono-fluorination of a-keto esters. OTf = trifluoromethanesulfonate.
Tetrahedron: Asymmetry, 2010
As a part of our research project on hard anion-late transition metal complexes as mild acid–base... more As a part of our research project on hard anion-late transition metal complexes as mild acid–base catalysts, we describe herein that CuII hydroxo complexes having chiral N-substituted-diaminocyclohexanes are mild and selective catalysts, which are applicable to the catalytic asymmetric conjugate addition of α-keto esters to nitroolefins. The reaction proceeded diastereoselectively without the detectable formation of self-aldol products, affording the corresponding
Journal of the American Chemical Society, 2005
The Japan Society of Applied Physics, 2019
Applied Physics Express
Control of the carrier density with high doping levels is a fundamental technology in semiconduct... more Control of the carrier density with high doping levels is a fundamental technology in semiconductor processing. However, unavoidable structural disorder in organic semiconductors can be introduced by chemical doping methods. Here, we synthesize a novel class of ionic polymers that generate a quasi-permanent electric field, and demonstrate that organic semiconductors in proximity to the ionic polymer can be electrostatically doped with significantly high carrier densities up to 5.6 × 10 13 cm −2 , which results in a low sheet resistance of ca. 60 kΩ. Electret doping presented here is expected to lead to an in-depth understanding of electric phase transitions in organic semiconductors.
Nature Communications
Chiral metal catalysts have been widely applied to asymmetric transformations. However, the elect... more Chiral metal catalysts have been widely applied to asymmetric transformations. However, the electronic structure of the catalyst and how it contributes to the activation of the substrate is seldom investigated. Here, we report an empirical approach for providing insights into the catalytic activation process in the distorted Ni(II)-catalysed asymmetric [3 þ 2] cycloaddition of a-ketoesters. We quantitatively characterize the bonding nature of the catalyst by means of electron density distribution analysis, showing that the distortion around the Ni(II) centre makes the dz 2 orbital partially 'naked', wherein the labile acetate ligand is coordinated with electrostatic interaction. The electron-deficient dz 2 orbital and the acetate act together to deprotonate the a-ketoester, generating the (L)-Ni(II)-enolate. The solid and solution state analyses, together with theoretical calculations, strongly link the electronic structure of the centrochiral octahedral Ni(II) complex and its catalytic activity, depicting a cooperative mechanism of enolate binding and outer sphere hydrogen-bonding activation.
Tetrahedron Letters, Jul 1, 2009
Advanced Synthesis Catalysis, Nov 2, 2010
Since the incorporation of fluorine into biologically active compounds often enhances the propert... more Since the incorporation of fluorine into biologically active compounds often enhances the properties of the parent compounds, there is a considerable demand for efficient enantioselective fluorination reactions. Over the past decade, a range of metal-catalyzed and organocatalyzed fluorination reactions has been developed. Nowadays, fluorine can be catalytically introduced into many compounds in good yield and with high enantioselectivity, and the scope of these reactions is broad. Herein, we review recent progress in the field of catalytic enantioselective fluorination reactions, including their scope and mechanism. 1 Introduction 2 Metal Catalysis 2.1 Fluorination of b-Dicarbonyl Compounds 2.2 Fluorination of b-Ketophosphonates 2.3 a-Fluorination of a-Cyanophosphonates and a-Cyano Esters 2.4 Mechanistic Considerations 2.5 Oxindole Derivatives 2.6 a-Arylacetic Acid Derivatives 3 Organocatalysis 3.
Advanced Synthesis Catalysis, Feb 15, 2011
ABSTRACT An organocatalytic enantioselective aziridination reaction of α,β-unsaturated aldehydes ... more ABSTRACT An organocatalytic enantioselective aziridination reaction of α,β-unsaturated aldehydes including aromatic substrates using N-arenesulfonyloxycarbamates in the presence of diphenylprolinol triethylsilyl ether and sodium carbonate or sodium acetate is described.