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101.
Nucleophilic para-fluorination of substituted anilines to afford 4-fluorocyclohexadieneimine derivatives is achieved in the presence of hypervalent iodine and pyridinium polyhydrogen fluoride. 相似文献
102.
Dr. Aurélien Adenot Dr. Lucile Anthore-Dalion Dr. Emmanuel Nicolas Jean-Claude Berthet Dr. Pierre Thuéry Dr. Thibault Cantat 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(72):18047-18053
An air-tolerant Cu-catalyzed sulfonylative Hiyama cross-coupling reaction enabling the formation of diaryl sulfones is described. Starting from aryl silanes, DABSO and aryliodides, the reaction tolerates a large variety of polar functional groups (amines, ketones, esters, aldehydes). Control experiments coupled with DFT calculations shed light on the mechanism, characterized by the formation of a Cu(I)-sulfinate intermediate via fast insertion of a SO2 molecule. 相似文献
103.
Jean-Claude Tabet Chantal Prevost Anne Bouillot Josette Bastard Due Do Khae Manh Yves Tondeur 《Helvetica chimica acta》1986,69(4):806-815
A stereospecific and regioselective SN2 mechanism (Walden inversion) is observed during studies involving modified terpenoid epimeric diols in a high-pressure ion source using ammonia as a reagent gas. 相似文献
104.
This article covers 50 years of coordination chemistry of transition metal complexes and metal-sulfur aggregates involving thiolate-incorporating ligands by reviewing selected examples. The studies in the coordination chemistry of sulfur-rich ligands have been undoubtedly triggered and fed by the concomitant development of bioinorganic chemistry, particularly of iron-sulfur enzymes. The review is broken down in five sections, which examine complexes of increasing nuclearity, including binuclear complexes based on compartmental macrocyclic ligands. We show also how ligand engineering has allowed the researchers in the field to control the nuclearity of the complexes, which was a particularly difficult task for sulfur-based ligands, as thiolates show a strong tendency to coordinate to more than one metal cation at once. 相似文献
105.
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107.
My-Loan-Phung Le Fannie Alloin Pierre Strobel Jean-Claude Lepr��tre Laure Cointeaux Carlos P��rez del Valle 《Ionics》2011,18(9):817-827
Ionic liquids, ILs, based on fluorinated pyrrolidinium and piperidinium ammonium cations and imide anion were prepared and characterized. The physicochemical and electrochemical properties of these ILs including melting point, glass transition and degradation temperatures, viscosity, ionic conductivity, and electrochemical stability were determined and compared to alkyl pyrrolidinium and piperidinium ILs. The incorporation of a CF3 group instead of a CH3 induces an increase of the IL viscosity, thus a conductivity decrease. However, good ionic conductivity is obtained with fluorinated pyrrolidinium IL. Cyclic amine ILs with propyl alkyl chain or fluorinated ammonium exhibit very high electrochemical stability toward oxidation. The effect of the addition of LiTFSI on the IL properties was studied with the same methodology. 相似文献
108.
109.
Christine Gravier-Pelletier Jacques Dumas Yves Le Merrer Jean-Claude Depezay 《Journal of carbohydrate chemistry》2013,32(8):969-998
AbstractEnantiomerically pure α-hydroxy, α,β-dihydroxy and α,β-epoxyaldehydes, useful building blocks for the synthesis of acyclic oxygenated fatty acids metabolites, were synthetized via epoxybutanediol acetonide starting from the commercially available L-ascorbic and D-isoascorbic acids. 相似文献
110.
Saoussen Zeror Jacqueline Collin Jean-Claude Fiaud Louisa Aribi Zouioueche 《Tetrahedron: Asymmetry》2010,21(9-10):1211-1215
In the search for green chemistry methods for the enantioselective reduction of ketoesters Saccharomyces cerevisiae- and ruthenium-catalyzed reactions in water have been investigated. The highest enantiomeric excesses for the reduction of α- and β-ketoesters have been obtained by S. cerevisiae. Chiral ruthenium catalysts are active for the reduction of all ketoesters with low to moderate enantioselectivities depending on the nature of the substrate and ligand. Interestingly, for several substrates both enantiomers of the hydroxyesters have been obtained according either to the catalytic method or to the structure of the ligand. 相似文献