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Palladium-catalyzed diastereo- and enantioselective formal [3 + 2]-cycloadditions of substituted vinylcyclopropanes.

ABSTRACT: We describe a palladium-catalyzed diastereo- and enantioselective formal [3 + 2]-cycloaddition between substituted vinylcyclopropanes and electron-deficient olefins in the form of azlactone- and Meldrum's acid alkylidenes to give highly substituted cyclopentane products. By modulation of the electronic properties of the vinylcyclopropane and the electron-deficient olefin, high levels of stereoselectivity were obtained. The remote stereoinduction afforded by the catalyst, distal from the chiral pocket generated by the ligand, is proposed to be the result of a new mechanism invoking the Curtin-Hammett principle.

SUBMITTER: Trost BM

PROVIDER: S-EPMC3495600 | biostudies-literature | 2012 Oct

REPOSITORIES: biostudies-literature

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Palladium-catalyzed diastereo- and enantioselective formal [3 + 2]-cycloadditions of substituted vinylcyclopropanes.

Trost Barry M BM Morris Patrick J PJ Sprague Simon J SJ

Journal of the American Chemical Society 20121010 42

We describe a palladium-catalyzed diastereo- and enantioselective formal [3 + 2]-cycloaddition between substituted vinylcyclopropanes and electron-deficient olefins in the form of azlactone- and Meldrum's acid alkylidenes to give highly substituted cyclopentane products. By modulation of the electronic properties of the vinylcyclopropane and the electron-deficient olefin, high levels of stereoselectivity were obtained. The remote stereoinduction afforded by the catalyst, distal from the chiral p ...[more]

PMID: 23030714

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