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Three-step synthesis of an annulated ?-carboline via palladium catalysis.

ABSTRACT: The synthesis of ?-carbolines is a mature field, yet new methods are desirable to introduce new functionality onto the core scaffold. We describe the incorporation of an additional fused ring onto the ?-carboline via a novel palladium-catalyzed, one-pot Sonogashira coupling/intramolecular [2+2+2] cyclization. This method generates three rings in one flask and produces an annulated ?-carboline in 80% yield. A preliminary mechanistic study into the sequence of events is described, which confirms an unprecedented catalytic role for palladium.

SUBMITTER: Mulcahy SP

PROVIDER: S-EPMC3861870 | biostudies-literature | 2013 Nov

REPOSITORIES: biostudies-literature

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Three-step synthesis of an annulated β-carboline via palladium catalysis.

Mulcahy Seann P SP Varelas Jonathan G JG

Tetrahedron letters 20131101 48

The synthesis of β-carbolines is a mature field, yet new methods are desirable to introduce new functionality onto the core scaffold. We describe the incorporation of an additional fused ring onto the β-carboline via a novel palladium-catalyzed, one-pot Sonogashira coupling/intramolecular [2+2+2] cyclization. This method generates three rings in one flask and produces an annulated β-carboline in 80% yield. A preliminary mechanistic study into the sequence of events is described, which confirms a ...[more]

PMID: 24347695

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