In Situ Generation of Ylides for Tandem Oxidation-Olefination Reactions of Unactivated Diols
作者:Andrew Graham、David Phillips
DOI:10.1055/s-2008-1042799
日期:——
An efficient desymmetrization of diols is achieved using phosphonium salts which undergo deprotonation in the presence of a hindered amine base and manganese dioxide to produce α,β-unsaturated hydroxy esters in good yields.
Diol desymmetrization as an approach to the synthesis of unsymmetrical dienyl diesters
作者:David J. Phillips、Kathryn S. Pillinger、Wei Li、Angela E. Taylor、Andrew E. Graham
DOI:10.1016/j.tet.2007.07.089
日期:2007.10
The tandem oxidation/Wittig olefination of unactivated diols utilizing manganese dioxide produces α,β-unsaturated hydroxy esters in high yields in a highly effective desymmetrization process. The formation of small quantities of the corresponding lactones suggests that the reaction may proceed through a lactol intermediate in some cases. The α,β-unsaturated hydroxy esters are transformed into symmetrical
Desymmetrization of diols by a tandem oxidation/Wittig olefination reaction
作者:David J. Phillips、Kathryn S. Pillinger、Wei Li、Angela E. Taylor、Andrew E. Graham
DOI:10.1039/b602329k
日期:——
Diols are desymmetrized by a tandem oxidation/Wittig olefination to give alpha,beta-unsaturated hydroxy esters without the requirement for protecting group strategies; the alpha,beta-unsaturated hydroxy esters are transformed into dienyl diesters using a second oxidation/Wittig olefination sequence using PCC.