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Mild and selective base-free C-H arylation of heteroarenes: experiment and computation.

ABSTRACT: A mild and selective C-H arylation strategy for indoles, benzofurans and benzothiophenes is described. The arylation method engages aryldiazonium salts as arylating reagents in equimolar amounts. The protocol is operationally simple, base free, moisture tolerant and air tolerant. It utilizes low palladium loadings (0.5 to 2.0 mol% Pd), short reaction times, green solvents (EtOAc/2-MeTHF or MeOH) and is carried out at room temperature, providing a broad substrate scope (47 examples) and excellent selectivity (C-2 arylation for indoles and benzofurans, C-3 arylation for benzothiophenes). Mechanistic experiments and DFT calculations support a Heck-Matsuda type coupling mechanism.

SUBMITTER: Gemoets HPL

PROVIDER: S-EPMC5356503 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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Mild and selective base-free C-H arylation of heteroarenes: experiment and computation.

Gemoets Hannes P L HPL Kalvet Indrek I Nyuchev Alexander V AV Erdmann Nico N Hessel Volker V Schoenebeck Franziska F Noël Timothy T

Chemical science 20160905 2

A mild and selective C-H arylation strategy for indoles, benzofurans and benzothiophenes is described. The arylation method engages aryldiazonium salts as arylating reagents in equimolar amounts. The protocol is operationally simple, base free, moisture tolerant and air tolerant. It utilizes low palladium loadings (0.5 to 2.0 mol% Pd), short reaction times, green solvents (EtOAc/2-MeTHF or MeOH) and is carried out at room temperature, providing a broad substrate scope (47 examples) and excellent ...[more]

PMID: 28451243

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