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One-pot synthesis of 1-alkyl-1H-indazoles from 1,1-dialkylhydrazones via aryne annulation.

ABSTRACT: The reaction of readily accessible 1,1-dialkylhydrazones with commercially available o-(trimethylsilyl)aryl triflates provides a direct one-step route to pharmaceutically important 1-alkylindazoles. The products are obtained in high yields by one-pot NCS-chlorination/aryne annulation or Ac(2)O-acylation/deprotection/aromatization protocols.

SUBMITTER: Markina NA

PROVIDER: S-EPMC3764999 | biostudies-literature | 2012 Mar

REPOSITORIES: biostudies-literature

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One-pot synthesis of 1-alkyl-1H-indazoles from 1,1-dialkylhydrazones via aryne annulation.

Markina Nataliya A NA Dubrovskiy Anton V AV Larock Richard C RC

Organic & biomolecular chemistry 20120216 12

The reaction of readily accessible 1,1-dialkylhydrazones with commercially available o-(trimethylsilyl)aryl triflates provides a direct one-step route to pharmaceutically important 1-alkylindazoles. The products are obtained in high yields by one-pot NCS-chlorination/aryne annulation or Ac(2)O-acylation/deprotection/aromatization protocols. ...[more]

PMID: 22337070

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