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Iridium-catalyzed regioselective and enantioselective allylation of trimethylsiloxyfuran.

ABSTRACT: We report the regio- and enantioselective allylation of an ester enolate, trimethylsiloxyfuran. This enolate reacts at the 3-position with linear aromatic allylic carbonates or aliphatic allylic benzoates to form the branched substitution products in the presence of a metallacyclic iridium catalyst. This process provides access to synthetically important 3-substituted butenolides in enantioenriched form. Stoichiometric reactions of the allyliridium intermediate suggest that the trimethylsiloxyfuran is activated by the carboxylate leaving group.

SUBMITTER: Chen W

PROVIDER: S-EPMC3487469 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature

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Iridium-catalyzed regioselective and enantioselective allylation of trimethylsiloxyfuran.

Chen Wenyong W Hartwig John F JF

Journal of the American Chemical Society 20120911 37

We report the regio- and enantioselective allylation of an ester enolate, trimethylsiloxyfuran. This enolate reacts at the 3-position with linear aromatic allylic carbonates or aliphatic allylic benzoates to form the branched substitution products in the presence of a metallacyclic iridium catalyst. This process provides access to synthetically important 3-substituted butenolides in enantioenriched form. Stoichiometric reactions of the allyliridium intermediate suggest that the trimethylsiloxyfu ...[more]

PMID: 22954355

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