Simple and Efficient TiCl4-Mediated Synthesis of Biaryls via Arylmagnesium Compounds

Oxidative self-coupling reactions of various arylmagnesium bromides with TiCl4 affords the corresponding symmetric biaryls in moderate to good yields at 0°C or lower. Tributylmagnesate-induced halogen–magnesium exchange of aryl halides followed by the coupling reaction provides biaryls in good yields under mild conditions. This method can achieve a one-pot synthesis of biaryls containing functional groups such as esters, amides, or nitriles.