Catalytic Enantioselective Synthesis of 3,4-Polyfused Oxindoles with Quaternary All-Carbon Stereocenters: A Rh-Catalyzed C–C Activation Approach
作者:Bo Qiu、Xiao-Tong Li、Jian-Yu Zhang、Jun-Ling Zhan、Shuang-Ping Huang、Tao Xu
DOI:10.1021/acs.orglett.8b03412
日期:2018.12.7
The first Rh-catalyzed enantioselective synthesis of a 3,4-polyfused oxindole ring system enabled by carboacylation of acrylic amides based on C–C activation is reported. This transformation provides a new entry to access 3,4-polyfused oxindoles bearing quaternary stereocenters. Tri- to pentacyclic 3,4-fused oxindoles were asymmetrically generated in good yields (up to 95%) with good to excellent enantioselectivity
据报道,第一个Rh催化的3,4-polyfused oxindole环系统的对映选择性合成是通过基于CC活化的丙烯酸酰胺的碳酰化实现的。这种转变为进入带有四级立体中心的3,4-多聚羟吲哚提供了新的机会。三到五环的3,4-稠合的吲哚以不对称的产率(高达95%)产生,并具有良好或优异的对映选择性(88%–97%ee)。分六个步骤完成了对木苯二酚A的第一次总合成的应用,总产率为14%。