Synthesis of β,γ‐unsaturated ketones with quaternary centers through regioselective hydroacylation of allenes with acyl chlorides

Abstract

The one‐pot synthesis of β,γ‐unsaturated ketones bearing all‐carbon quaternary centers at the α‐position via a highly regioselective hydroacylation of allenes using acyl chlorides and aluminum hydride is reported. The Cu‐catalyzed hydroalumination of 1,1‐disubstituted and 1,1,3‐trisubstituted allenes with diisobutylaluminum hydride resulted in allylaluminum reagents that underwent regioselective acylation in the presence of acid chlorides. Various derivatives of allenes and acyl chlorides were compatible with this process, and α‐quaternary ketones were obtained in high yields with excellent regioselectivity.