Enantiodivergent Preparation of Optically Active Oxindoles Having a Stereogenic Quaternary Carbon Center at the C3 Position via the Lipase-Catalyzed Desymmetrization Protocol: Effective Use of 2-Furoates for Either Enzymatic Esterification or Hydrolysis
作者:Shuji Akai、Toshiaki Tsujino、Emi Akiyama、Kouichi Tanimoto、Tadaatsu Naka、Yasuyuki Kita
DOI:10.1021/jo035749h
日期:2004.4.1
the C3 position and a different N-protective group, were readily prepared by the lipase-catalyzed desymmetrization protocol. Thus, the transesterification of the prochiral diols 3a−h with 1-ethoxyvinyl 2-furoate 5 was catalyzed by Candida rugosa lipase to give (R)-(+)-2a−h (68−99% ee), in which the use of a mixed solvent, iPr2O (diisopropyl ether)−THF, was crucial. The same lipase also effected the