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Weak Bronsted acid-thiourea co-catalysis: enantioselective, catalytic protio-Pictet-Spengler reactions.

ABSTRACT: The development of one-pot imine formation and asymmetric Pictet-Spengler reactions cocatalyzed by a chiral thiourea and benzoic acid is described. Optically active tetrahydro-beta-carbolines, ubiquitous structural motifs in biologically active natural products, are obtained in high ee directly from tryptamine and aldehyde precursors.

SUBMITTER: Klausen RS

PROVIDER: S-EPMC2664157 | biostudies-literature | 2009 Feb

REPOSITORIES: biostudies-literature

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Weak Brønsted acid-thiourea co-catalysis: enantioselective, catalytic protio-Pictet-Spengler reactions.

Klausen Rebekka S RS Jacobsen Eric N EN

Organic letters 20090201 4

The development of one-pot imine formation and asymmetric Pictet-Spengler reactions cocatalyzed by a chiral thiourea and benzoic acid is described. Optically active tetrahydro-beta-carbolines, ubiquitous structural motifs in biologically active natural products, are obtained in high ee directly from tryptamine and aldehyde precursors. ...[more]

PMID: 19178157

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