Construction of quaternary carbon centers by KOtBu-catalyzed α-homoallylic alkylation of lactams with 1,3-dienes

Abstract

We report a KOtBu-catalyzed α-homoallylic alkylation of lactams with 1,3-dienes. With this transition metal-free and atom-economical protocol, a variety of α-homoallylic alkylated lactams bearing α-quaternary carbon centers were formed in a 2,1-addition manner with excellent regioselectivity. A cation–π interaction between the in situ-generated potassium enolate and the diene is proposed to play a key role in accelerating this transformation.