Divergent NHC-Catalyzed Oxidative Transformations of 3-Bromoenal: Selective Synthesis of 2<i>H</i>-Pyran-2-ones and Chiral Dihydropyranones
作者:Gang Wang、Xia Chen、Gaohan Miao、Weijun Yao、Cheng Ma
DOI:10.1021/jo400950j
日期:2013.6.21
A selectivesynthesis of either 2H-pyran-2-ones (4) or chiral dihydropyranones (6) from the same substrates of 3-bromoenals and 1,3-dicarbonyl compounds upon oxidative N-heterocyclic carbene catalysis is presented. It is shown that the oxidative transformation of 3-bromoenals under NHC catalyst can be well controlled to proceed through two pathways, i.e., elimination of reducible β-bromide or by an
Palladium-Catalyzed Intramolecular Oxidative Heck Cyclization and Its Application toward a Synthesis of (±)-β-Cuparenone Derivatives Supported by Computational Studies
oxidative cyclization of substituted homoallylic alcohols to form cyclic keto compounds under palladium-catalyzed conditions is described. The reaction has practical applications in the synthesis of sesquiterpenes. The mechanism of cyclization, the key step in the tandemreaction, was analyzed by using density functional theory calculations. A novel and efficient intramolecular oxidative cyclization of substituted
A modular approach toward the synthesis of 2,4-disubstituted pyridines
作者:Raju Singha、Shubhendu Dhara、Jayanta K. Ray
DOI:10.1016/j.tetlet.2013.06.092
日期:2013.9
A number of 2,4-disubstituted pyridines have been synthesized using alpha,beta,gamma,delta-unsaturated aldehydes and ammonium chloride in the presence of triethylamine in acetonitrile solvent at 80 degrees C under air balloon. (C) 2013 Elsevier Ltd. All rights reserved.