Asymmetric dihydroxylation and hydrogenation approaches to the enantioselective synthesis of R-(+)-α-lipoic acid
作者:T.T Upadhya、M.D Nikalje、A Sudalai
DOI:10.1016/s0040-4039(01)00734-1
日期:2001.7
asymmetric synthesis of methyl (S)-6,8-dihydroxyoctanoate (5) and (S)-6,8-dimethylsulfonyloxyoctane-1-carboxylic acid (13), key precursors to R-(+)-α-lipoic acid (6) is described using OsO4-catalyzed asymmetric dihydroxylation and Ru-catalyzed asymmetric hydrogenation, respectively, as the key steps in the reaction sequence. These methods lead to an efficient formal synthesis of R-(+)-α-lipoic acid in 90%
R -(+)-α-硫辛酸的关键前体(S)-6,8-二羟基辛酸甲酯(5)和(S)-6,8-二甲基磺酰氧基辛烷-1-羧酸(13)的不对称合成图6)分别描述了使用OsO 4催化的不对称二羟基化和Ru催化的不对称氢化作为反应序列中的关键步骤。这些方法导致R -(+)-α-硫辛酸在90%ee中的有效形式合成。