Ring Contraction of 2-Chlorocyclohexanone with Grignard Reagents

Abstract

The reaction of 2-chlorocyclohexanone with phenylmagnesium bromide in refluxing tetrahydrofuran unexpectedly afforded the ring-contracted product, cyclopentyl phenyl ketone, as the main product in moderate yield. The reactivities of several cyclic 2-haloketones were examined.