N-heterocyclic carbene and Bronsted acid cooperative catalysis: asymmetric synthesis of trans-γ-lactams.

ABSTRACT: An efficient enantioselective approach to form trans-γ-lactams in up to 99% yield, 93% ee, and >20/1 dr using unactivated imines has been developed. The cyclohexyl-substituted azolium and the weak base sodium o-chlorobenzoate are most suitable for this transformation. Notably, the process involves cooperative catalysis by an N-heterocyclic carbene and a Brønsted acid.

SUBMITTER: Zhao X 

PROVIDER: S-EPMC3155423 | biostudies-literature | 2011 Aug

REPOSITORIES: biostudies-literature