New advances in olefin homo and copolymerization using neutral, single component palladium/nickel complexes ligated by a phosphine-sulfonate

Abstract

Use of catalysts for olefin homo- and copolymerization has received growing attention in recent decades. Most polyolefins especially polyethylene and polypropylene are currently produced in the presence of transition-metal catalysts. So far, late transition-metal catalysts particularly nickel and palladium-based complexes have attracted great attention and various ligands have been employed in the structure of these catalysts. In this contribution, nickel and palladium-based complexes with symmetrical cationic α-diimine (as Brookhart catalysts) and non-symmetrical neutral phosphine-sulfonate ligands (as Drent catalysts) have been extensively utilized as olefin (co)polymerization catalysts. Unlike classic α-diimine complexes, the generation of highly linear ethylene/polar monomer copolymers, prepared in the absence of co-catalyst by phosphine-sulfonate palladium/nickel catalysts poses an interesting case. The outstanding features of phosphine-sulfonate-based catalysts motivated many researchers to focus on these catalysts. In this context, several review articles have covered various aspects of this class of catalysts. Considering the importance of phosphine-sulfonate-based catalysts, in this mini-review, we wish to address recent advances of the neutral, single component palladium/nickel complexes bearing phosphine–sulfonate ligands for olefin (co)polymerization with polar monomers.