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Enantioselective synthesis of ?-oxy amides via Umpolung amide synthesis.

ABSTRACT: ?-Oxy amides are prepared through enantioselective synthesis using a sequence beginning with a Henry addition of bromonitromethane to aldehydes and finishing with Umpolung Amide Synthesis (UmAS). Key to high enantioselection is the finding that ortho-iodo benzoic acid salts of the chiral copper(II) bis(oxazoline) catalyst deliver both diastereomers of the Henry adduct with high enantiomeric excess, homochiral at the oxygen-bearing carbon. Overall, this approach to ?-oxy amides provides an innovative complement to alternatives that focus almost entirely on the enantioselective synthesis of ?-oxy carboxylic acids.

SUBMITTER: Leighty MW

PROVIDER: S-EPMC3477818 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature

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Enantioselective synthesis of α-oxy amides via Umpolung amide synthesis.

Leighty Matthew W MW Shen Bo B Johnston Jeffrey N JN

Journal of the American Chemical Society 20120911 37

α-Oxy amides are prepared through enantioselective synthesis using a sequence beginning with a Henry addition of bromonitromethane to aldehydes and finishing with Umpolung Amide Synthesis (UmAS). Key to high enantioselection is the finding that ortho-iodo benzoic acid salts of the chiral copper(II) bis(oxazoline) catalyst deliver both diastereomers of the Henry adduct with high enantiomeric excess, homochiral at the oxygen-bearing carbon. Overall, this approach to α-oxy amides provides an innova ...[more]

PMID: 22967461

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Umpolung reactivity in amide and peptide synthesis.

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