Enantioselective Organocatalytic Michael−Wittig−Michael−Michael Reaction: Dichotomous Construction of Pentasubstituted Cyclopentanecarbaldehydes and Pentasubstituted Cyclohexanecarbaldehydes
作者:Bor-Cherng Hong、Roshan Y. Nimje、Cheng-Wei Lin、Ju-Hsiou Liao
DOI:10.1021/ol1030487
日期:2011.3.18
reagent) to nitroalkenes, followed by a reaction with ethyl formylformate and cinnamaldehydes, or formaldehyde and cinnamaldehydes, provided the respective pentasubstituted cyclopentanecarbaldehydes bearing a quaternary carbon center and pentasubstituted cyclohexanecarbaldehydes having five contiguous stereocenters with excellent enantioselectivities (up to >99% ee).
将甲乙氧基亚甲基三苯基磷烷(一种Wittig试剂)迈克尔加成到硝基烯烃中,然后与甲醛甲酸酯和肉桂醛或甲醛和肉桂醛反应,得到各自带有季碳中心的五取代环戊烷甲醛和具有五个连续立体中心且具有优异对映体选择的五取代环己烷甲醛(对映体选择> 99%ee)。