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Umpolung of Michael acceptors catalyzed by N-heterocyclic carbenes.

ABSTRACT: N-Heterocyclic carbenes can catalyze beta-alkylations of a range of alpha,beta-unsaturated esters, amides, and nitriles that bear pendant leaving groups to form a variety of ring sizes. In this process, the nucleophilic catalyst transiently transforms the normally electrophilic beta carbon into a nucleophilic site through an unanticipated addition-tautomerization sequence.

SUBMITTER: Fischer C

PROVIDER: S-EPMC2553003 | biostudies-literature | 2006 Feb

REPOSITORIES: biostudies-literature

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Umpolung of Michael acceptors catalyzed by N-heterocyclic carbenes.

Fischer Christian C Smith Sean W SW Powell David A DA Fu Gregory C GC

Journal of the American Chemical Society 20060201 5

N-Heterocyclic carbenes can catalyze beta-alkylations of a range of alpha,beta-unsaturated esters, amides, and nitriles that bear pendant leaving groups to form a variety of ring sizes. In this process, the nucleophilic catalyst transiently transforms the normally electrophilic beta carbon into a nucleophilic site through an unanticipated addition-tautomerization sequence. ...[more]

PMID: 16448117

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