Palladium-catalyzed carboncarbon coupling reactions using aryl Grignards

Coupling reactions using Pd(PPh3)4 were investigated with a number of electron donating and electron withdrawing substituents. High yields were obtained with both types of substituents. In competitive reactions the electron-withdrawing group -NO2 reacted preferentially over the electron donating groups. When the starting halides were converted to Grignard reagents, high yields were obtained for some hindered electron-withdrawing groups.