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A dual Lewis base activation strategy for enantioselective carbene-catalyzed annulations.

ABSTRACT: A dual activation strategy integrating N-heterocyclic carbene (NHC) catalysis and a second Lewis base has been developed. NHC-bound homoenolate equivalents derived from ?,?-unsaturated aldehydes combine with transient reactive o-quinone methides in an enantioselective formal [4 + 3] fashion to access 2-benzoxopinones. The overall approach provides a general blueprint for the integration of carbene catalysis with additional Lewis base activation modes.

SUBMITTER: Izquierdo J

PROVIDER: S-EPMC3746556 | biostudies-literature | 2013 Jul

REPOSITORIES: biostudies-literature

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A dual Lewis base activation strategy for enantioselective carbene-catalyzed annulations.

Izquierdo Javier J Orue Ane A Scheidt Karl A KA

Journal of the American Chemical Society 20130711 29

A dual activation strategy integrating N-heterocyclic carbene (NHC) catalysis and a second Lewis base has been developed. NHC-bound homoenolate equivalents derived from α,β-unsaturated aldehydes combine with transient reactive o-quinone methides in an enantioselective formal [4 + 3] fashion to access 2-benzoxopinones. The overall approach provides a general blueprint for the integration of carbene catalysis with additional Lewis base activation modes. ...[more]

PMID: 23829462

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