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Palladium-catalyzed asymmetric allylic alkylation of meso- and dl-1,2-divinylethylene carbonate.

ABSTRACT: The palladium-catalyzed asymmetric allylic alkylation of a 1:1 mixture of dl- and meso-1,2-divinylethylene carbonate is reported. For the first time, both the ionization and nucleophilic addition steps of the catalytic cycle act as enantiodiscriminating steps to give a single product in high enantiomeric excess. The reactions proceed in >98% ee to efficiently generate useful chiral building blocks from acrolein. The absolute and relative configurations of iso-cladospolide B and 11-epi-iso-cladospolide B were verified by total synthesis, solving an apparent discrepancy in the literature.

SUBMITTER: Trost BM

PROVIDER: S-EPMC2531165 | biostudies-literature | 2006 Mar

REPOSITORIES: biostudies-literature

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Palladium-catalyzed asymmetric allylic alkylation of meso- and dl-1,2-divinylethylene carbonate.

Trost Barry M BM Aponick Aaron A

Journal of the American Chemical Society 20060301 12

The palladium-catalyzed asymmetric allylic alkylation of a 1:1 mixture of dl- and meso-1,2-divinylethylene carbonate is reported. For the first time, both the ionization and nucleophilic addition steps of the catalytic cycle act as enantiodiscriminating steps to give a single product in high enantiomeric excess. The reactions proceed in >98% ee to efficiently generate useful chiral building blocks from acrolein. The absolute and relative configurations of iso-cladospolide B and 11-epi-iso-clados ...[more]

PMID: 16551099

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