Living isomerization polymerizations of alkenylcyclohexane with camphyl α-diimine nickel catalysts

Late Transition Metal Catalysts with Chelating Amines for Olefin Polymerization

Polyolefins are the most consumed polymeric materials extensively used in our daily life and are usually generated by coordination polymerization in the polyolefin industry. Olefin polymerization catalysts containing transition metal–organic compound combinations are undoubtedly crucial for the development of the polyolefin industry. The nitrogen donor atom has attracted considerable interest and is widely used in combination with the transition metal for the fine-tuning of the chemical environment around the metal center. In addition to widely reported olefin polymerization catalysts with imine and amide donors (sp2 hybrid N), late transition metal catalysts with chelating amine donors (sp3 hybrid N) for olefin polymerization have never been reviewed. In this review paper, we focus on late transition metal (Ni, Pd, Fe, and Co) catalysts with chelating amines for olefin polymerization. A variety of late transition metal catalysts bearing different neutral amine donors are surveyed for olefin polymerization, including amine–imine, amine–pyridine, α-diamine, and [N, N, N] tridentate ligands with amine donors. The relationship between catalyst structure and catalytic performance is also encompassed. This review aims to promote the design of late transition metal catalysts with unique chelating amine donors for the development of high-performance polyolefin materials.

Combining hydrogen bonding interactions with steric and electronic modifications for thermally robust α-diimine palladium catalysts toward ethylene (co)polymerization

Thermally robust α-diimine palladium catalysts are highly active for ethylene (co)polymerization at high temperatures by steric and electronic modifications in combination with hydrogen bonding interactions.

Living Chain-Walking (Co)Polymerization of Propylene and 1-Decene by Nickel α-Diimine Catalysts

Homo- and copolymers of propylene and 1-decene were synthesized by controlled chain-walking (co)polymerization using phenyl substituted α-diimine nickel complexes activated with modified methylaluminoxane (MMAO). This catalytic system was found to polymerize propylene in a living fashion to furnish high molecular weight ethylene-propylene (EP) copolymers. The copolymerizations proceeded to give high molecular weight P/1-decene copolymers with narrow molecular weight distribution (Mw/Mn ≈ 1.2), which indicated a living nature of copolymerization at room temperature. The random copolymerization results indicated the possibility of precise branched structure control, depending on the polymerization temperature and time.

A continuing legend: the Brookhart-type α-diimine nickel and palladium catalysts

Here we will summarize some of the recent advances in α-diimine ligand developments, as well as some new and challenging monomers that this class of catalysts can address through these ligand improvements.