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Cyclic ketimines as superior electrophiles for NHC-catalyzed homoenolate additions with broad scope and low catalyst loadings.

ABSTRACT: Cyclic sulfonyl imines derived from ketones were identified as stable and readily prepared compounds that serve as superior electrophiles for N-heterocyclic carbene (NHC)-catalyzed annulations with alpha,beta-unsaturated aldehydes to afford highly substituted gamma-lactams. Their superior reactivity and properties are highlighted by the first example of NHC-catalyzed reactions of enals with low catalyst loadings (0.5 mol %) and broad substrate scope encompassing alkyl, aryl, and heteroaromatic substituents. These findings and supporting studies suggest an alternative, ene-like mechanism rather than the catalytic generation of a catalyst-bound homoenolate equivalent.

SUBMITTER: Rommel M

PROVIDER: S-EPMC2631935 | biostudies-literature | 2008 Dec

REPOSITORIES: biostudies-literature

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Cyclic ketimines as superior electrophiles for NHC-catalyzed homoenolate additions with broad scope and low catalyst loadings.

Rommel Michael M Fukuzumi Takeo T Bode Jeffrey W JW

Journal of the American Chemical Society 20081201 51

Cyclic sulfonyl imines derived from ketones were identified as stable and readily prepared compounds that serve as superior electrophiles for N-heterocyclic carbene (NHC)-catalyzed annulations with alpha,beta-unsaturated aldehydes to afford highly substituted gamma-lactams. Their superior reactivity and properties are highlighted by the first example of NHC-catalyzed reactions of enals with low catalyst loadings (0.5 mol %) and broad substrate scope encompassing alkyl, aryl, and heteroaromatic s ...[more]

PMID: 19053399

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