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Updated: Mar 7, 2026
A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Doubly Regioselective C-H Hydroarylation of Unsymmetrical Alkynes Using Carboxylates as Deciduous Directing Groups
Agostino Biafora1, Bilal A Khan2, Janet Bahri3
1FB Chemie und Forschungszentrum OPTIMAS, Technische Universität Kaiserslautern , Erwin-Schroedinger-Strasse Geb 52-54, 67663 Kaiserslautern, Germany.
Abstract:
A catalyst system composed of [(C6Me6)RuCl2]2, potassium carbonate/guanidine carbonate, and mesitoic acid efficiently promotes the doubly regioselective C-H hydroarylation of unsymmetrical alkynes. The process involves carboxylate-directed ortho-C-H bond activation followed by regioselective addition to the alkyne C-C triple bond with concerted decarboxylation. This action of the carboxylate as a deciduous directing group ensures exclusive monovinylation with high selectivity for the (E)-1,2-diarylalkene.
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