Room Temperature Nickel(II) Complexes [(4-MeOC6H4)Ni-(PCy3)2OTs and Ni(PCy3)2X2]-Catalyzed Cross-Coupling Reactions of Aryl/Alkenyl Sulfonates with Arylboronic Acids

Room temperature nickel(II) complexes [(4-MeOC6H4)Ni(PCy3)(2)OTs and Ni(PCy3)(2)X-2 (X=Cl, Br)]-catalyzed cross-coupling reactions of aryl/alkenyl sulfonates with arylboronic acids are described. The nickel(II) complex (4-MeOC6H4)Ni(PCy3)(2)OTs proved to be a general catalyst for the Suzuki-Miyaura cross-coupling reactions of aryl sulfonates with arylboronic acids. By limiting the amount of the water in the initial catalytically active Ni(0) species generation stage, Ni(PCy3)(2)X-2 (X=Cl, Br) could also be efficient catalysts for the cross-coupling reactions a variety of aryl/activated alkenyl tosylates with arylboronic acids. The mild reaction condition, the easy availability of the catalysts and excellent coupling yields make these catalyst systems potentially useful in organic synthesis.