钯催化溴代酚的[2+2+1]去芳构螺环化反应

Pd-Catalyzed Dearomative Spirocyclization of Bromophenols via [2+2+1] Strategy

在零价钯的催化作用下,以简单且商品化的溴代苯酚为研究目标,炔烃作为偶联片段,通过[2+2+1]反应策略,实现了苯酚的去芳构螺环化转化,合成了一系列新颖的含有季碳中心的螺环骨架化合物.该方法采用的底物简单易得,具有宽泛的底物范围,并且可以获得较优的收率;在非对称炔烃方面,能以优异的区域选择性(>19∶1 rr)实现这一转化,极大地拓宽了苯酚去芳构化的研究范围.

A novel palladium(0)-catalyzed dearomative spirocyclization reaction of bromophenols has been developed for building a series of spirocyclic architectures containing a quaternary carbon center via[2+2+1] strategy.This method employs inexpensive bromophenols and easily accessible alkynes.It exhibits a broad substrate scope in good yields.Notably,this transformation can be realized with high regioselectivity (>19:1 rr) when using unsymmetrical alkynes,which greatly expands the research scope of phenol dearomatization.