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Unusually reactive and selective carbonyl ylides for three-component cycloaddition reactions.

ABSTRACT: Conditions are described for the Rh-catalyzed formation of highly functionalized dihydro- and tetrahydrofuran products via three-component reactions of aldehydes, alpha-alkyl-alpha-diazoesters, and dipolarophiles. The alkyl-substituted carbonyl ylides that are generated in this fashion are highly reactive in cycloaddition reactions and display a scope of reactivity that is much broader than the three-component reactions of carbonyl ylides derived from ethyl diazoacetate or alpha-aryl-alpha-diazoesters. The reactions of alkyl-substituted carbonyl ylides proceed with high regioselectivity and diastereoselectivity that are rationalized in terms of an asynchronous, endo-selective transition state.

SUBMITTER: DeAngelis A

PROVIDER: S-EPMC2659807 | biostudies-literature | 2009 Jan

REPOSITORIES: biostudies-literature

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Unusually reactive and selective carbonyl ylides for three-component cycloaddition reactions.

DeAngelis Andrew A Taylor Michael T MT Fox Joseph M JM

Journal of the American Chemical Society 20090101 3

Conditions are described for the Rh-catalyzed formation of highly functionalized dihydro- and tetrahydrofuran products via three-component reactions of aldehydes, alpha-alkyl-alpha-diazoesters, and dipolarophiles. The alkyl-substituted carbonyl ylides that are generated in this fashion are highly reactive in cycloaddition reactions and display a scope of reactivity that is much broader than the three-component reactions of carbonyl ylides derived from ethyl diazoacetate or alpha-aryl-alpha-diazo ...[more]

PMID: 19128053

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