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Enantioselective Michael addition/iminium ion cyclization cascades of tryptamine-derived ureas.

ABSTRACT: A Michael addition/iminium ion cyclization cascade of enones with tryptamine-derived ureas under BINOL phosphoric acid (BPA) catalysis is reported. The cascade reaction tolerates a wide variety of easily synthesized tryptamine-derived ureas, including those bearing substituents on the distal nitrogen atom of the urea moiety, affording polyheterocyclic products in good yields and good to excellent enantioselectivities.

SUBMITTER: Aillaud I

PROVIDER: S-EPMC3931331 | biostudies-literature | 2013 Jun

REPOSITORIES: biostudies-literature

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Enantioselective Michael addition/iminium ion cyclization cascades of tryptamine-derived ureas.

Aillaud Isabelle I Barber David M DM Thompson Amber L AL Dixon Darren J DJ

Organic letters 20130530 12

A Michael addition/iminium ion cyclization cascade of enones with tryptamine-derived ureas under BINOL phosphoric acid (BPA) catalysis is reported. The cascade reaction tolerates a wide variety of easily synthesized tryptamine-derived ureas, including those bearing substituents on the distal nitrogen atom of the urea moiety, affording polyheterocyclic products in good yields and good to excellent enantioselectivities. ...[more]

PMID: 23721179

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