Ferrous salt-promoted homocoupling of arenediazonium tetrafluoroborates under mild conditions

A simple and efficient protocol has been developed for the synthesis of various symmetrical biaryls in good to excellent yields from the homocoupling reactions of arenediazonium salts with ferrous salt in carbon tetrachloride solution under mild reaction conditions. Moreover, the novel homocoupling has been demonstrated to proceed via an electron transfer reaction mechanism.