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Updated: Apr 21, 2026

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Indium-catalyzed intramolecular hydroarylation of aryl propargyl ethers
Lorena Alonso-Marañón1, M Montserrat Martínez, Luis A Sarandeses
1Departamento de Química Fundamental and Centro de Investigaciones Científicas Avanzadas (CICA), Universidade da Coruña, E-15071 A Coruña, Spain. sestelo@udc.es.
Abstract:
Indium(III) halides catalyze efficiently the intramolecular hydroarylation (IMHA) of aryl propargyl ethers. The reaction proceeds regioselectively with terminal and internal alkynes bearing electron-rich and electron-deficient substituents in the benzenes and alkynes affording only the 6-endo dig cyclization product. Additionally, a sequential indium-catalyzed IMHA and palladium-catalyzed Sonogashira coupling can be performed in one reaction vessel. Experiments with deuterium support a mechanism through electrophilic aromatic substitution.
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