Nickel-Catalyzed Propylene/Polar Monomer Copolymerization.

Nickel complexes bearing bidentate alkylphophine-phenolate ligands were synthesized and applied to the polymerization of propylene and the copolymerization of propylene and polar monomers. Therein, the use of bulky alkyl substituents on the phosphorus atom was crucial for the formation of highly regioregular polypropylenes. Theoretical calculations suggested that the 1,2-insertion of propylene is favored over the 2,1-insertion in these nickel-catalyzed (co)polymerization reactions.