New copper-mediated O-arylations of phenols with arylstannanes

A novel method for the synthesis of diaryl ethers with phenols and arylstannanes under mild conditions is described. This copper-mediated O-arylation is feasible using DMAP in acetonitrile and is complementary to the use of boronic acids as aryl donors. The reaction is tolerant of a wide range of substituents and sterically hindered coupling partners.