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Asymmetric synthesis of functionalized cyclopentanones via a multicatalytic secondary amine/N-heterocyclic carbene catalyzed cascade sequence.

ABSTRACT: A one-pot, asymmetric multicatalytic formal [3+2] reaction between 1,3-dicarbonyls and alpha,beta-unsaturated aldehydes is described. The multicatalytic process involves a secondary amine catalyzed Michael addition followed by a N-heterocyclic carbene catalyzed intramolecular crossed benzoin reaction to afford densely functionalized cyclopentanones with high enantioselectivities. The reaction proceeds with a variety of alkyl and aryl enals as well as a range of 1,3-dicarbonyls (diketones and beta-ketoesters). The functionalized products are obtained from cheap, readily available starting materials in a rapid and efficient manner in a one-pot, one-step operation.

SUBMITTER: Lathrop SP

PROVIDER: S-EPMC2785226 | biostudies-literature | 2009 Sep

REPOSITORIES: biostudies-literature

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Asymmetric synthesis of functionalized cyclopentanones via a multicatalytic secondary amine/N-heterocyclic carbene catalyzed cascade sequence.

Lathrop Stephen P SP Rovis Tomislav T

Journal of the American Chemical Society 20090901 38

A one-pot, asymmetric multicatalytic formal [3+2] reaction between 1,3-dicarbonyls and alpha,beta-unsaturated aldehydes is described. The multicatalytic process involves a secondary amine catalyzed Michael addition followed by a N-heterocyclic carbene catalyzed intramolecular crossed benzoin reaction to afford densely functionalized cyclopentanones with high enantioselectivities. The reaction proceeds with a variety of alkyl and aryl enals as well as a range of 1,3-dicarbonyls (diketones and bet ...[more]

PMID: 19731910

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