Mechanistic Study of Copper-Catalyzed Aerobic Oxidative Coupling of Arylboronic Esters and Methanol: Insights into an Organometallic Oxidase Reaction

摘要

Copper-catalyzed oxidative and nonoxidative coupling reactions have been known for more than a century. Prominent early examples include the Glaser coupling of terminal alkynes and Ullmann-Goldberg cross-coupling reactions of aryl halides. Among a wide range of new copper-catalyzed coupling reactions reported in recent years, one class with growing importance is the Cu-catalyzed oxidative coupling of boronic acids and heteroatom nucleophiles (eq 1), first reported by Chan, Evans, and Lam in 1998. These reactions typically employ milder reaction conditions than the analogous Ullmann-Goldberg reactions, and their applications have expanded significantly since the initial reports.