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Dynamic kinetic asymmetric transformations of ?-stereogenic ?-ketoesters by direct aldolization.

ABSTRACT: Dynamic kinetic asymmetric transformations (DyKAT) of racemic ?-bromo-?-keto esters by direct aldolization of nitromethane and acetone provide access to fully substituted ?-glycolic acid derivatives bearing a ?-stereocenter. The aldol adducts are obtained in excellent yield with high relative and absolute stereocontrol under mild reaction conditions. Mechanistic studies determined that the reactions proceed through a facile catalyst-mediated racemization of the ?-bromo-?-keto esters under a DyKAT Type I manifold.

SUBMITTER: Corbett MT

PROVIDER: S-EPMC3921961 | biostudies-literature | 2014 Jan

REPOSITORIES: biostudies-literature

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Dynamic kinetic asymmetric transformations of β-stereogenic α-ketoesters by direct aldolization.

Corbett Michael T MT Johnson Jeffrey S JS

Angewandte Chemie (International ed. in English) 20131112 1

Dynamic kinetic asymmetric transformations (DyKAT) of racemic β-bromo-α-keto esters by direct aldolization of nitromethane and acetone provide access to fully substituted α-glycolic acid derivatives bearing a β-stereocenter. The aldol adducts are obtained in excellent yield with high relative and absolute stereocontrol under mild reaction conditions. Mechanistic studies determined that the reactions proceed through a facile catalyst-mediated racemization of the β-bromo-α-keto esters under a DyKA ...[more]

PMID: 24222195

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