Rh(III)-Catalyzed Annulation of 2-Biphenylboronic Acid with Diverse Activated Alkenes
作者:Bingxian Liu、Lingyun Yang、Zhenzhen Dong、Junbiao Chang、Xingwei Li
DOI:10.1021/acs.orglett.1c02597
日期:2021.9.17
the reductive elimination process prior to protonolysis, affording the [4 + 2] annulated products instead of the simple 1,4-addition product. Seven-membered rings were obtained when disubstituted cyclopropenones were employed. Bridged cycles were isolated from the coupling of 2-biphenylboronic acid with benzoquinones as a result of 2-fold Michael additions. The substrate scopes were found to be broad
已经实现了铑(III)催化的 2-联苯硼酸与三类活化烯烃的环化,通过金属转移引发的 C-H 活化合成稠合或桥连的环状骨架。在 2-联苯硼酸与 CF 3取代的烯酮的环状偶联中,庞大的环戊二烯基配体 (Cp t Bu) 在催化剂中被证明有效地促进质子分解之前的还原消除过程,提供 [4 + 2] 环化产物而不是简单的 1,4-加成产物。当使用双取代的环丙烯酮时,得到七元环。由于 2 倍迈克尔加成,从 2-联苯硼酸与苯醌的偶联中分离出桥接环。发现底物范围很广,在耐气条件下的产率高达 99%。