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Asymmetric N-heterocyclic carbene catalyzed addition of enals to nitroalkenes: controlling stereochemistry via the homoenolate reactivity pathway to access ?-lactams.

ABSTRACT: An asymmetric intermolecular reaction between enals and nitroalkenes to yield ?-nitroesters has been developed, catalyzed by a novel chiral N-heterocyclic carbene. Key to this work was the development of a catalyst that favors the ?-nitroester pathway over the established Stetter pathway. The reaction proceeds in high stereoselectivity and affords the previously unreported syn diastereomer. We also report an operationally facile two-step, one-pot procedure for the synthesis of ?-lactams.

SUBMITTER: White NA

PROVIDER: S-EPMC3723348 | biostudies-literature | 2013 Jun

REPOSITORIES: biostudies-literature

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Asymmetric N-heterocyclic carbene catalyzed addition of enals to nitroalkenes: controlling stereochemistry via the homoenolate reactivity pathway to access δ-lactams.

White Nicholas A NA DiRocco Daniel A DA Rovis Tomislav T

Journal of the American Chemical Society 20130528 23

An asymmetric intermolecular reaction between enals and nitroalkenes to yield δ-nitroesters has been developed, catalyzed by a novel chiral N-heterocyclic carbene. Key to this work was the development of a catalyst that favors the δ-nitroester pathway over the established Stetter pathway. The reaction proceeds in high stereoselectivity and affords the previously unreported syn diastereomer. We also report an operationally facile two-step, one-pot procedure for the synthesis of δ-lactams. ...[more]

PMID: 23713683

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