Silver-mediated homocoupling of arylboronic acids

Here we describe a homocoupling reaction of arylboronic acid facilitated by silver carbonate, which proceeds smoothly in MeOH even at ambient temperature. The reaction exhibits broad functional group compatibility, affording a variety of symmetrical biaryls in satisfactory yields. Silver nanoparticles formed in situ serve as an accelerator in this process. Moreover, initial mechanistic investigations suggest that this transformation may occur via a radical mechanism.