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Rhodium-catalyzed enantioselective vinylogous addition of enol ethers to vinyldiazoacetates.

ABSTRACT: A highly asymmetric vinylogous addition of acyclic silyl enol ethers to siloxyvinyldiazoacetate is described. The reaction features a diastereoselective 1,4-siloxy group migration event. Products are obtained in up to 97% ee. When more sterically crowded silyl enol ethers are employed, an enantioselective formal [3+2] cycloaddition becomes the dominant reaction pathway. Control experiments reveal the (Z)-olefin geometry to be critical for high levels of enantiocontrol.

SUBMITTER: Smith AG

PROVIDER: S-EPMC3549400 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

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Rhodium-catalyzed enantioselective vinylogous addition of enol ethers to vinyldiazoacetates.

Smith Austin G AG Davies Huw M L HM

Journal of the American Chemical Society 20121029 44

A highly asymmetric vinylogous addition of acyclic silyl enol ethers to siloxyvinyldiazoacetate is described. The reaction features a diastereoselective 1,4-siloxy group migration event. Products are obtained in up to 97% ee. When more sterically crowded silyl enol ethers are employed, an enantioselective formal [3+2] cycloaddition becomes the dominant reaction pathway. Control experiments reveal the (Z)-olefin geometry to be critical for high levels of enantiocontrol. ...[more]

PMID: 23098215

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