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Updated: Mar 3, 2026

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Mild and selective base-free C-H arylation of heteroarenes: experiment and computation
Hannes P L Gemoets1, Indrek Kalvet2, Alexander V Nyuchev1,3
1Department of Chemical Engineering and Chemistry , Micro Flow Chemistry & Process Technology , Eindhoven University of Technology , Den Dolech 2 , 5612 AZ Eindhoven , The Netherlands .
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.
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