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The Mannich reaction of malonates with simple imines catalyzed by bifunctional cinchona alkaloids: enantioselective synthesis of beta-amino acids.

ABSTRACT: We describe the first efficient, direct asymmetric Mannich reactions with malonates and N-Boc aryl and alkyl imines by cooperative hydrogen-bonding catalysis with a cinchona alkaloid bearing a thiourea functionality. We have also extended the scope of this reaction to beta-ketoesters. The synthetic value of this new reaction is demonstrated in the establishment of a convergent enantioselective route toward the biologically important beta-amino acids under mild and air- and moisture-tolerant conditions.

SUBMITTER: Song J

PROVIDER: S-EPMC3172002 | biostudies-literature | 2006 May

REPOSITORIES: biostudies-literature

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The Mannich reaction of malonates with simple imines catalyzed by bifunctional cinchona alkaloids: enantioselective synthesis of beta-amino acids.

Song Jun J Wang Yi Y Deng Li L

Journal of the American Chemical Society 20060501 18

We describe the first efficient, direct asymmetric Mannich reactions with malonates and N-Boc aryl and alkyl imines by cooperative hydrogen-bonding catalysis with a cinchona alkaloid bearing a thiourea functionality. We have also extended the scope of this reaction to beta-ketoesters. The synthetic value of this new reaction is demonstrated in the establishment of a convergent enantioselective route toward the biologically important beta-amino acids under mild and air- and moisture-tolerant cond ...[more]

PMID: 16669669

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