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Enantioconvergent synthesis of functionalized ?-butyrolactones via (3 + 2)-annulation.

ABSTRACT: A dynamic kinetic resolution of ?-halo ?-keto esters in an asymmetric homoenolate reaction is described. A chiral N-hetereocyclic carbene catalyzes the a(3) ? d(3)-umpolung addition of ?,?-enals to racemic ?-keto esters, forming ?-butyrolactones with three contiguous stereocenters. The addition occurs with high regio-, diastereo-, and enantiocontrol. This methodology constitutes an intermolecular DKR process to set three stereocenters during the key bond forming event.

SUBMITTER: Goodman CG

PROVIDER: S-EPMC4304455 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature

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Enantioconvergent synthesis of functionalized γ-butyrolactones via (3 + 2)-annulation.

Goodman C Guy CG Walker Morgan M MM Johnson Jeffrey S JS

Journal of the American Chemical Society 20141223 1

A dynamic kinetic resolution of β-halo α-keto esters in an asymmetric homoenolate reaction is described. A chiral N-hetereocyclic carbene catalyzes the a(3) → d(3)-umpolung addition of α,β-enals to racemic α-keto esters, forming γ-butyrolactones with three contiguous stereocenters. The addition occurs with high regio-, diastereo-, and enantiocontrol. This methodology constitutes an intermolecular DKR process to set three stereocenters during the key bond forming event. ...[more]

PMID: 25533016

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