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Bronsted acid catalysis of achiral enamine for regio- and enantioselective nitroso aldol synthesis.

ABSTRACT: Two types of chiral Brønsted acid catalysts have been shown to catalyze regio- and enantioselective nitroso aldol synthesis between nitrosobenzene and achiral enamine. The combination of Brønsted acidity and amine moiety of enamine realizes complete regioselectivity with high enantioselectivity. After a survey of Brønsted acid catalysts, 1-naphthyl glycolic acid is found to be optimal in the O-nitroso aldol pathway, while 1-naphthyl TADDOL is the best catalyst for the N-nitroso aldol pathway. This is based on our finding on the control of regioselectivity by changing the amine moiety of enamine and the choice of Brønsted acidity.

SUBMITTER: Momiyama N

PROVIDER: S-EPMC1460970 | biostudies-literature | 2005 Feb

REPOSITORIES: biostudies-literature

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Bronsted acid catalysis of achiral enamine for regio- and enantioselective nitroso aldol synthesis.

Momiyama Norie N Yamamoto Hisashi H

Journal of the American Chemical Society 20050201 4

Two types of chiral Brønsted acid catalysts have been shown to catalyze regio- and enantioselective nitroso aldol synthesis between nitrosobenzene and achiral enamine. The combination of Brønsted acidity and amine moiety of enamine realizes complete regioselectivity with high enantioselectivity. After a survey of Brønsted acid catalysts, 1-naphthyl glycolic acid is found to be optimal in the O-nitroso aldol pathway, while 1-naphthyl TADDOL is the best catalyst for the N-nitroso aldol pathway. Th ...[more]

PMID: 15669829

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