The desymmetrisation of prochiral α,α-dicyanoalkenes via tandem MichaelâMichael addition reactions with α,β-unsaturated ketones catalysed by 9-amino-9-deoxyepicinchona alkaloids was investigated, from which bicyclic products bearing four stereogenic centers were afforded in a single operation with high stereoselectivities (>99% de, up to >99.5% ee).
研究了通过9-
氨基-9-脱氧表
金鸡纳碱催化的与α,β-不饱和酮的串联迈克尔-迈克尔加成反应,使α,β-二
氰基烯烃的非对映异构体非对映化,由此在单次操作中获得了具有四个立体中心的双环产物,立体选择性高(de>99%,ee>99.5%)。