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Updated: Mar 3, 2026

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Iridium-Catalyzed, Weakly Coordination-Assisted Ortho-Alkynylation of (Hetero)aromatic Carboxylic Acids without
Changpeng Chen1, Pei Liu1, Jinghua Tang1
1Frontier Institute of Science and Technology, Xi'an Jiaotong University , Xi'an 710054, China.
Abstract:
It is reported a weakly coordination-assisted alkynylation of aryl and heteroaryl carboxylic acids with iridium catalysis. The reaction is catalyzed by [{Cp*IrCl2}2] complex without cyclization, forming ortho-alkynylated aryl and heteroaryl carboxylic acids, and features high functional group tolerance and broad substrate scope under an air atmosphere. 2-(Hetero)aryl-substituted acetic acids were amenable to the alkynylation by forming an unusual six-membered ring cycloiridiated intermediate.
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