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

ABSTRACT: An efficient enantioselective approach to form trans-?-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

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

Zhao Xiaodan X DiRocco Daniel A DA Rovis Tomislav T

Journal of the American Chemical Society 20110725 32

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. ...[more]

PMID: 21780842

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