Stereoselective Synthesis of Three Isomers of tert-Butyl 5-Hydroxy-4-methyl-3-oxohexanoate through Alcohol Dehydrogenase-Catalyzed Dynamic Kinetic Resolution
作者:Steffen Lüdeke、Michael Richter、Michael Müller
DOI:10.1002/adsc.200800619
日期:2009.1
Regioselective reduction of the 5-keto group of tert-butyl 4-methyl-3,5-dioxohexanoate (1) leads to a stereodiad of tert-butyl 5-hydroxy-4-methyl-3-oxohexanoate (2). Alcohol dehydrogenases from Lactobacillus brevis (LBADH), Rhodococcus sp. (RS 1-ADH) and Saccharomyces cerevisiae (YGL157w) reduce 1 under dynamic kinetic resolution conditions, thereby establishing two chiral carbons with a single reduction
区域选择性还原4-甲基-3,5-二氧己酸叔丁基酯的5-酮基(1)导致5-羟基-4-甲基-3-氧杂己酸叔丁基酯的立体二胺(2)。来自短乳杆菌(LBADH),红球菌属(Rhodococcus sp。)的醇脱氢酶。(RS 1-ADH)和啤酒酵母(YGL157w)在动态动力学拆分条件下还原1,从而在一个还原步骤中建立两个手性碳。尽管先前已经显示,减少LBADH的1所立体选择性地导致顺式- (4-小号,5 - [R )- 2,乙醇脱氢酶介导的动态动力学拆分现在可轻松获得syn-(4 R,5 S)-2(RS 1-ADH; 97.6%ee,syn:反= 92:8,转化率66%,分离产率37% )和抗-(4 S,5 S)-2(YGL157w; 90%ee,抗:syn = 93:7,转化率为64%,分离产率为42%)。因此,当还原为1时,选择性地形成四种可能的立体异构体中的三种。