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Asymmetric synthesis of anti-?-amino-?-hydroxy esters via dynamic kinetic resolution of ?-amino-?-keto esters.

ABSTRACT: A method for the asymmetric synthesis of enantioenriched anti-?-hydroxy-?-amino acid derivatives by enantioconvergent reduction of the corresponding racemic ?-keto esters is presented. The requisite ?-keto esters are prepared via Mannich addition of ethyl diazoacetate to imines followed by oxidation of the diazo group with Oxone. Implementation of a recently developed dynamic kinetic resolution of ?-substituted-?-keto esters via Ru(II)-catalyzed asymmetric transfer hydrogenation provides the title motif in routinely high diastereo- and enantioselectivity.

SUBMITTER: Goodman CG

PROVIDER: S-EPMC3766400 | biostudies-literature | 2013 May

REPOSITORIES: biostudies-literature

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Asymmetric synthesis of anti-β-amino-α-hydroxy esters via dynamic kinetic resolution of β-amino-α-keto esters.

Goodman C Guy CG Do Dung T DT Johnson Jeffrey S JS

Organic letters 20130430 10

A method for the asymmetric synthesis of enantioenriched anti-α-hydroxy-β-amino acid derivatives by enantioconvergent reduction of the corresponding racemic α-keto esters is presented. The requisite α-keto esters are prepared via Mannich addition of ethyl diazoacetate to imines followed by oxidation of the diazo group with Oxone. Implementation of a recently developed dynamic kinetic resolution of β-substituted-α-keto esters via Ru(II)-catalyzed asymmetric transfer hydrogenation provides the tit ...[more]

PMID: 23631467

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