Development of Cross-Coupling Reactions Including Electro-oxidative Processes and Their Applications to the Synthesis of π-Extended Compounds

Abstract

An electrochemical method to synthesize cationic palladium complexes has been developed. Their counter anions could be changed readily by the electrolyte. The reaction could be incorporated into electro-oxidative palladium catalyzed reactions, such as Wacker-type reaction, homo-coupling of arylboronic acids, oxidative Sonogashira-type coupling, and Glaser-type coupling of terminal alkynes. These reactions exhibited a wide scope and a variety of products were obtained in high yields due to high activity of electrogenerated palladium species. We also developed site-selective sequential reactions by the integration of the electro-oxidative coupling reactions with non-electrochemical reactions. The reaction site could be controlled completely by the on/off application of electricity.