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Nucleophilic ortho-allylation of pyrroles and pyrazoles: an accelerated Pummerer/thio-Claisen rearrangement sequence.

ABSTRACT: Arylsulfinyl groups direct the metal-free, regiospecific, nucleophilic ortho-allylation of pyrroles and pyrazoles. Mechanistic studies support the intermediacy of allylsulfonium salts that undergo facile thio-Claisen rearrangement onto the heterocyclic ring, giving products of coupling. The strategy has been adapted to allow regiospecific propargylation of the heterocyclic substrates.

SUBMITTER: Eberhart AJ

PROVIDER: S-EPMC3819180 | biostudies-literature | 2013 Aug

REPOSITORIES: biostudies-literature

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Nucleophilic ortho-allylation of pyrroles and pyrazoles: an accelerated Pummerer/thio-Claisen rearrangement sequence.

Eberhart Andrew J AJ Cicoira Claudio C Procter David J DJ

Organic letters 20130715 15

Arylsulfinyl groups direct the metal-free, regiospecific, nucleophilic ortho-allylation of pyrroles and pyrazoles. Mechanistic studies support the intermediacy of allylsulfonium salts that undergo facile thio-Claisen rearrangement onto the heterocyclic ring, giving products of coupling. The strategy has been adapted to allow regiospecific propargylation of the heterocyclic substrates. ...[more]

PMID: 23855635

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