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Stereospecific decarboxylative allylation of sulfones.

ABSTRACT: Allyl sulfonylacetic esters undergo highly stereospecific, palladium-catalyzed decarboxylative allylation. The reaction allows the stereospecific formation of tertiary homoallylic sulfones in high yield. In contrast to related reactions that proceed at -100 degrees C and require highly basic preformed organometallics, the decarboxylative coupling described herein occurs under mild nonbasic conditions and requires no stoichiometric additives. Allylation of the intermediate alpha-sulfonyl anion is more rapid than racemization, leading to a highly enantiospecific process. Density functional theory calculations indicate that the barrier for racemization is 9.9 kcal/mol, so the barrier for allylation must be <9.9 kcal/mol.

SUBMITTER: Weaver JD

PROVIDER: S-EPMC2935626 | biostudies-literature | 2010 Sep

REPOSITORIES: biostudies-literature

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Stereospecific decarboxylative allylation of sulfones.

Weaver Jimmie D JD Ka Being J BJ Morris David K DK Thompson Ward W Tunge Jon A JA

Journal of the American Chemical Society 20100901 35

Allyl sulfonylacetic esters undergo highly stereospecific, palladium-catalyzed decarboxylative allylation. The reaction allows the stereospecific formation of tertiary homoallylic sulfones in high yield. In contrast to related reactions that proceed at -100 degrees C and require highly basic preformed organometallics, the decarboxylative coupling described herein occurs under mild nonbasic conditions and requires no stoichiometric additives. Allylation of the intermediate alpha-sulfonyl anion is ...[more]

PMID: 20715821

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