Radical‐Polar Crossover Annulation: A Platform for Accessing Polycyclic Cyclopropanes
作者:John A. Milligan、Kevin L. Burns、Anthony V. Le、Viktor C. Polites、Zheng‐Jun Wang、Gary A. Molander、Christopher B. Kelly
DOI:10.1002/adsc.201901051
日期:2020.1.7
to the cyclopropanation of olefins that are embedded within bicyclic scaffolds. Whereas these systems are notoriously recalcitrant toward classical cyclopropanation approaches, RPC cyclopropanation can be executed with ease, leading to polycarbocyclic and polyheterocyclic cyclopropanes. The cyclopropanation proceeds through a photoredox‐enabled Giese‐type radical addition followed by an intramolecular
光氧化还原介导的自由基/极性交叉(RPC)工艺提供了具有挑战性的环空解决方案。在本文中,我们描述了一种嵌入双环支架内的烯烃的环丙烷化方法。众所周知,这些系统对经典的环丙烷化方法难以抗拒,而RPC环丙烷化可以轻松实施,从而形成多碳环和多杂环环丙烷。环丙烷化的过程是通过添加光致氧化还原的Giese型自由基进行的,然后在新戊基离去基团上进行分子内阴离子取代反应。