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Stereodivergency of triazolium and imidazolium-derived NHCs for catalytic, enantioselective cyclopentane synthesis.

ABSTRACT: Chiral triazolium- and imidazolium-derived N-heterocyclic carbene catalysts promote the direct annulation of alpha,beta-unsaturated aldehydes and achiral alpha-hydroxy enones to afford cyclopentane-fused lactones with high enantioselectivity. Remarkably, otherwise structurally identical imidazolium and triazolium precatalysts afford different major products. These studies provide both an efficient entry to valuable chiral structures and a dramatic demonstration of stereodivergency of chiral imidazolium versus triazolium-derived N-heterocyclic carbene catalysts.

SUBMITTER: Kaeobamrung J

PROVIDER: S-EPMC2664100 | biostudies-literature | 2009 Feb

REPOSITORIES: biostudies-literature

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Stereodivergency of triazolium and imidazolium-derived NHCs for catalytic, enantioselective cyclopentane synthesis.

Kaeobamrung Juthanat J Bode Jeffrey W JW

Organic letters 20090201 3

Chiral triazolium- and imidazolium-derived N-heterocyclic carbene catalysts promote the direct annulation of alpha,beta-unsaturated aldehydes and achiral alpha-hydroxy enones to afford cyclopentane-fused lactones with high enantioselectivity. Remarkably, otherwise structurally identical imidazolium and triazolium precatalysts afford different major products. These studies provide both an efficient entry to valuable chiral structures and a dramatic demonstration of stereodivergency of chiral imid ...[more]

PMID: 19175349

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