Regioselective Vinylation of Remote Unactivated C(sp3 )-H Bonds: Access to Complex Fluoroalkylated Alkenes

Abstract

Regioselective incorporation of a particular functional group into aliphatic sites by direct activation of unreactive C-H bonds is of great synthetic value. Despite advances in radical-mediated functionalization of C(sp³ )-H bonds by a hydrogen-atom transfer process, the site-selective vinylation of remote C(sp³ )-H bonds still remains underexplored. Reported herein is a new protocol for the regioselective vinylation of unactivated C(sp³ )-H bonds. The remote C(sp³ )-H activation is promoted by a C-centered radical instead of the commonly used N and O radicals. The reaction possesses high product diversity and synthetic efficiency, furnishing a plethora of synthetically valuable E alkenes bearing tri-/di-/mono-fluoromethyl and perfluoroalkyl groups.

Keywords: C−H activation; alcohols; fluorine; photocatalysis; radicals.