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Asymmetric Mannich synthesis of ?-amino esters by anion-binding catalysis.

ABSTRACT: We report a scalable, one-pot Mannich route to enantioenriched ?-amino esters by direct reaction of ?-chloroglycine ester as a practical imino ester surrogate. The reaction is promoted by a chiral aminothiourea, which is proposed to operate cooperatively by generating an iminium ion by chloride abstraction and an enolate by deprotonation, followed by highly stereoselective C-C bond formation between both reactive intermediates associated non-covalently within the catalyst framework.

SUBMITTER: Wasa M

PROVIDER: S-EPMC4183616 | biostudies-literature | 2014 Sep

REPOSITORIES: biostudies-literature

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Asymmetric Mannich synthesis of α-amino esters by anion-binding catalysis.

Wasa Masayuki M Liu Richard Y RY Roche Stéphane P SP Jacobsen Eric N EN

Journal of the American Chemical Society 20140908 37

We report a scalable, one-pot Mannich route to enantioenriched α-amino esters by direct reaction of α-chloroglycine ester as a practical imino ester surrogate. The reaction is promoted by a chiral aminothiourea, which is proposed to operate cooperatively by generating an iminium ion by chloride abstraction and an enolate by deprotonation, followed by highly stereoselective C-C bond formation between both reactive intermediates associated non-covalently within the catalyst framework. ...[more]

PMID: 25178040

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