Dual Brønsted Acid/Nucleophilic Activation of Carbonylimidazole Derivatives
作者:Stephen T. Heller、Tingting Fu、Richmond Sarpong
DOI:10.1021/ol300339q
日期:2012.4.20
Carbonylimidazole derivatives have been found to be highly active acylation reagents for esterification and amidation in the presence of pyridinium salts. These reactions are thought to involve both Bronsted acid and nucleophilic catalysis. This mode of activation has been applied to the synthesis of difficult to access oxazolidinones, as well as esters and amides. Finally, the use of pyridinium salts has been shown to accelerate the esterification of carboxylic acids with imidazole carbamates.
US4788277A
申请人:——
公开号:US4788277A
公开(公告)日:1988-11-29
US7999039B2
申请人:——
公开号:US7999039B2
公开(公告)日:2011-08-16
One-Pot Synthesis of Unsymmetrical N-Heterocyclic Carbene Ligands from<i>N</i>-(2-Iodoethyl)arylamine Salts
作者:B. A. Bhanu Prasad、Scott R. Gilbertson
DOI:10.1021/ol901189m
日期:2009.8.20
approach that provides symmetrical, unsymmetrical, and asymmetric N-heterocyclic carbene (NHC) ligands is reported. Reaction of iodoethanol with aniline provides N-(2-iodoethyl)arylamine salts that are then converted to the corresponding iodide. Reaction with aliphatic or aromatic amines followed by triethyl orthoformate was used to provide 26 different NHC ligands.