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Updated: Nov 20, 2025

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
Gold-Catalyzed Intermolecular Alkyne Oxyarylation for C3 Functionalization of Benzothiophenes
Paige A Rist1, Richard S Grainger1, Paul W Davies1
1School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, U.K.
Abstract:
C3-selective C-C bond formation on benzothiophenes is challenging, and few direct functionalization methods are available. A gold-catalyzed reaction of alkynes with benzothiophene S-oxides provides regioselective entry into C3-alkylated benzothiophenes with the C7-alkylated isomer as the minor product. This oxyarylation reaction works with alkyl and aryl alkynes and substituted and unsubstituted benzothiophenes. Mechanistic studies identify that sulfoxide inhibits the catalyst [DTBPAu(PhCN)]SbF6, which also degrades and forms the unreactive complex [(DTBP)2Au]SbF6.
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