Electrooxidative Iridium-Catalyzed Regioselective Annulation of Benzoic Acids with Internal Alkynes
Qi-Liang Yang1, Hong-Wei Jia1, Ying Liu1
1Henan Key Laboratory of Organic Functional Molecules and Drug Innovation, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China.
Abstract:
Electrochemically driven, Cp*Ir(III)-catalyzed regioselective annulative couplings of benzoic acids with alkynes have been established herein. The combination of iridium catalyst and electricity not only circumvents the need for stoichiometric amount of chemical oxidant, but also ensures broad reaction compatibility with a wide array of sterically and electronically diverse substrates. This electrochemical approach represents a sustainable strategy as an ideal alternative and supplement to the oxidative annulations methodology to be engaged in the synthesis of isocoumarin derivatives.
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