An α-Diaminoboryl Carbanion Assisted Stereoselective Single-Pot Preparation of α,β<i>-</i>Disubstituted Acrylonitriles
作者:Takashi Tomioka、Rambabu Sankranti、Trey G. Vaughan、Toshihide Maejima、Takayoshi Yanase
DOI:10.1021/jo201280x
日期:2011.10.7
An alpha-diaminoboryl carbanion-mediated one-pot olefination directly converts an acetonitrile or the homologous nitrile into a series of alpha,beta-disubstituted acrylonitriles in a stereoselective manner. The protocol involves the formation of an alpha-substituted alpha-diaminoboryl acetonitrile and subsequent olefination with an aldehyde. The use of an aryl or conjugated aldehyde preferentially leads to a (Z)-acrylonitrile, while an aliphatic aldehyde gave an (E)-isomer as a major product. Two complementary approaches, a linear method and a divergent method, are developed.