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Rh-catalyzed intermolecular cyclopropanation with alpha-alkyl-alpha-diazoesters: catalyst-dependent chemo- and diastereoselectivity.

ABSTRACT: A Rh-catalyzed procedure for the cyclopropanation of alkenes with alpha-alkyl-alpha-diazoesters is described. With dirhodium tetraoctanoate, the predominant pathway is beta-hydride elimination. While a number of sterically demanding carboxylate ligands serve to avoid beta-hydride elimination, it was found that triphenylacetate (TPA) also imparts high diastereoselectivity.

SUBMITTER: Panne P

PROVIDER: S-EPMC2696156 | biostudies-literature | 2008 Jul

REPOSITORIES: biostudies-literature

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Rh-catalyzed intermolecular cyclopropanation with alpha-alkyl-alpha-diazoesters: catalyst-dependent chemo- and diastereoselectivity.

Panne Patricia P DeAngelis Andrew A Fox Joseph M JM

Organic letters 20080612 14

A Rh-catalyzed procedure for the cyclopropanation of alkenes with alpha-alkyl-alpha-diazoesters is described. With dirhodium tetraoctanoate, the predominant pathway is beta-hydride elimination. While a number of sterically demanding carboxylate ligands serve to avoid beta-hydride elimination, it was found that triphenylacetate (TPA) also imparts high diastereoselectivity. ...[more]

PMID: 18547051

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