Palladium-Catalyzed Aerobic Oxidative Coupling of o-Xylene in Flow: A Safe and Scalable Protocol for Cross-Dehydrogenative Coupling

Herein, the first continuous cross-dehydrogenative homocoupling of an unactivated arene using oxygen as sole oxidant is reported. Employing micro reactor technology which enables the use of elevated temperatures and pressures leads to a boost of the catalytic reaction. Hence, a major reduction in reaction time is achieved. Due to the significance as precursor for MOFs as well as high-tech and high-value polymers, the study focused on the production of 3,4,3',4'-tramethyl-biphenyl.