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Thiourea-catalyzed enantioselective iso-Pictet-Spengler reactions.

ABSTRACT: A one-pot condensation of isotryptamines and aldehydes that affords enantiomerically enriched 4-substituted tetrahydro-?-carbolines is reported. The reaction is induced by a chiral thiourea/benzoic acid dual catalyst system. Purification of the N-Boc-protected products by trituration or crystallization provides the optically pure tetrahydro-?-carboline derivatives in a scalable and highly practical procedure.

SUBMITTER: Lee Y

PROVIDER: S-EPMC3206290 | biostudies-literature | 2011 Oct

REPOSITORIES: biostudies-literature

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Thiourea-catalyzed enantioselective iso-Pictet-Spengler reactions.

Lee Yunmi Y Klausen Rebekka S RS Jacobsen Eric N EN

Organic letters 20110915 20

A one-pot condensation of isotryptamines and aldehydes that affords enantiomerically enriched 4-substituted tetrahydro-γ-carbolines is reported. The reaction is induced by a chiral thiourea/benzoic acid dual catalyst system. Purification of the N-Boc-protected products by trituration or crystallization provides the optically pure tetrahydro-γ-carboline derivatives in a scalable and highly practical procedure. ...[more]

PMID: 21919478

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