Understanding the π-facial diastereoselectivity in the addition of chiral diaminophosphino(silyl)carbenes to activated olefins
作者:Ona Illa、Xavier Bagan、Antoine Baceiredo、Vicenç Branchadell、Rosa M. Ortuño
DOI:10.1016/j.tetasy.2008.10.021
日期:2008.10
The synthesis of a new chiral diaminophosphino(silyl)carbene, based on the use of (R,R)-cyclotlexane-trans-1,2-diamine, is described. Its reaction with methyl acrylate afforded a cyclopropane derivative as a single diastereomer. The diastereoselectivity in the addition reactions between olefins and chiral carbenes derived from C-2-symmetric diamines has also been Studied by theoretical calculations, which establish that it has a steric origin; we report a rationale to predict the absolute configuration of the adducts. (C) 2008 Elsevier Ltd. All rights reserved.