Catalytic Carbon Insertion into the β-Vinyl C–H Bond of Cyclic Enones with Alkyl Diazoacetates

Abstract

The first example of the boron Lewis acid catalyzed C(sp2)-H functionalization of cyclic enones was achieved using diazoacetates. The insertion of the carbon atom of diazoacetates utilizes BF3•Et2O or a newly designed oxazaborolidinium ion as a catalyst to afford β-functionalized cyclic enones from simple cyclic enones in a single step and high yields. The reaction mechanism was investigated with deuterium labeled 2-cyclohexen-1-one.