Utilizing a copper foam electrode as the catalyst in Sonogashira C-H activation coupling reactions for the electro-oxidation synthesis of diphenylethyne derivatives

Abstract

In recent years, there have been significant advancements in Copper-catalyzed Sonogashira coupling reactions, employing both traditional and electro-oxidation methods for synthesizing diphenylethyne derivatives. This study focuses on the progress achieved through the utilization of copper foam electro-catalyzed Sonogashira coupling reactions in the synthesis of diphenylethyne derivatives 4(a-q) and provides insights into the future prospects of this field. The paper emphasizes the development of efficient copper foam catalysts, the optimization of reaction conditions, and potential applications of electro-oxidation reaction copper-catalyzed Sonogashira coupling in various fields, including materials chemistry and organic synthesis. The integration of electro-oxidation reactions into copper-catalyzed Sonogashira coupling reactions presents a promising approach for the efficient synthesis of diphenylethyne derivatives. The future trajectory of this field involves further advancements in catalyst design, reaction optimization, and the exploration of new applications for diphenylethyne derivatives across diverse scientific disciplines. This investigation specifically explores the electro-oxidation process of the Sonogashira reaction, utilizing a copper foam cathode and graphite anode in isopropyl alcohol (iPrOH) as the solvent and weak base. Sodium bromide (NaBr) serves as an economical and readily available electrolyte and reagent under green and sustainable conditions. The successful synthesis of a variety of diphenylethyne derivatives 4(a-q) was achieved, with notable yields ranging from 83% to 92%.