A series of imidazolium ionic liquids were designed and synthesized by the reaction of imidazole derivatives with alkyl bromides. These ionic liquids were applied to catalyze the reaction of CO2 and epoxides. A detailed investigation was carried out on the relationship between catalytic activities and catalyst structures. The result showed that phenolic hydroxyl-functionalized imidazolium ionic liquids containing both phenolic hydroxyl and C2-H were highly efficient catalysts. Meanwhile, the spatial positions of the phenolic hydroxyl and C2-H in the imidazolium also exhibited great effect on the catalytic efficiencies, and the order of catalytic activity was meta-isomer > ortho-isomer. > para-isomer. NMR titration and DFT calculations showed a synergetic effect, which C2-H and phenolic hydroxyl cooperatively activated epoxides by hydrogen bonds, was crucial for the reaction to proceed smoothly under mild conditions. In addition, the TOF of the most active catalyst 3-(3-phenolic hydroxyl)-1-butyl-imidazolium bromide (IL-2) reached to 900 h(-1) in the reaction of CO2 and epichlorohydrin under the reaction conditions of 0.1 mol% catalyst, 1 MPa CO2, 120 degrees C and 1 h. (C) 2016 Elsevier B.V. All rights reserved.
Synthesis and investigation of inhibitory activities of imidazole derivatives against the metallo-β-lactamase IMP-1
of β-lactam antibiotics with an inhibitor. So far, no clinically available inhibitors of metallo β-lactamases (MBLs) reported and the clinically inhibitors of serine β-lactamase are useless for MBLs. Accordingly, finding a potent inhibitor of the MBLs being very important. In this study, imidazole derivatives primarily were synthesized and their inhibitory activity were measured. Later in silico binding
Design of Ionic Phosphites for Catalytic Hydrocyanation Reaction of 3-Pentenenitrile in Ionic Liquids†
作者:Christophe Vallée、Yves Chauvin、Jean-Marie Basset、Catherine C. Santini、Jean-Christophe Galland
DOI:10.1002/adsc.200505086
日期:2005.11
aminophosphites or three cationic groups prepared by reaction of phosphorustrichloride with imidazolium phenols are reported. The catalytic hydrocyanation reaction of 3-pentenenitrile (3PN) into adiponitrile has been performed in the presence of Ni(0) with ionic phosphite ligands, and a Lewis acid in biphasic ionic liquid/organic solvent system. The screening of several original cationic phosphites