Use of Chiraphos as a Highly Efficient Ligand in the Nickel(II)-catalyzed Cross-coupling Polymerization for the synthesis of Poly(1,4-arylene)s

Chiraphos (2,3-diphenylphosphinobutane) serves as a highly effective ligand for nickel catalysts in cross-coupling polymerization reactions. Nickel(II) catalyst efficiently promotes the cross-coupling polymerization of 2,5-differently substituted 1,4-dihalobenzene particularly bearing a sterically congested substituent at the side chain affording the corresponding poly(1,4-phenylene). Such a highly active catalyst allowed the polymerization with a diverse degree of polymerization with controlled molecular weight.