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A Mild and General Larock Indolization Protocol for the Preparation of Unnatural Tryptophans.

ABSTRACT: A mild and general protocol for the Pd(0)-catalyzed heteroannulation of o-bromoanilines and alkynes is described. Application of a Pd(0)/P((t)Bu)3 catalyst system enables the efficient coupling of o-bromoanilines at 60 °C, mitigating deleterious side reactions and enabling access to a broad range of useful unnatural tryptophans. The utility of this new protocol is demonstrated in the highly convergent total synthesis of the bisindole natural product (-)-aspergilazine A.

SUBMITTER: Chuang KV

PROVIDER: S-EPMC5505074 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature

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A Mild and General Larock Indolization Protocol for the Preparation of Unnatural Tryptophans.

Chuang Kangway V KV Kieffer Madeleine E ME Reisman Sarah E SE

Organic letters 20160906 18

A mild and general protocol for the Pd(0)-catalyzed heteroannulation of o-bromoanilines and alkynes is described. Application of a Pd(0)/P((t)Bu)3 catalyst system enables the efficient coupling of o-bromoanilines at 60 °C, mitigating deleterious side reactions and enabling access to a broad range of useful unnatural tryptophans. The utility of this new protocol is demonstrated in the highly convergent total synthesis of the bisindole natural product (-)-aspergilazine A. ...[more]

PMID: 27598827

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