Chlorocyclization/cycloreversion of allylic alcohols to vinyl chlorides

Abstract

The semipinacol rearrangement of allylic alcohols and their derivatives via a three-membered chloronium intermediate is a well-established procedure for the synthesis of vinyl chlorides. Herein, we report a new mix-and-go general procedure involving chlorocyclization/cycloreversion of allylic alcohols with N-chlorobenzenesulfonimide (NCSI), affording remote carbonyl vinyl chlorides. This procedure proceeds through a three-membered chloronium intermediate, which chlorocyclizes to form oxetane, and then catalyst-free cycloreversion takes place under mild reaction conditions with broad functional group tolerance and good to excellent yields.