Synthesis and ethylene oligomerization performance of nickel metal catalysts based on quinoline-amine ligands

The evolution of polyolefin catalysts has progressed from Ziegler-Natta catalysts to metallocene catalysts and, more recently, to non-metallocene catalysts. Nonmetallocene transition metal catalysts have emerged as a focal point in contemporary research, owing to their superior catalytic performance, structural diversity of ligand architectures, and well-defined single-site active centers. A variety of quinoline-based early transition metal catalysts have been demonstrated to exhibit superior catalytic performance. Among the non-metallocene transition metal catalysts, late transition metal catalysts exhibit distinct advantages in enabling the copolymerization of ethylene with polar monomers such as methyl methaNiylate (MMA), thereby facilitating the production of functional polyolefin materials. Based on these findings, this study designed and synthesized six SNN tridentate Ni catalysts, with selected representatives subjected to structural characterization, and used them in the ethylene zwitterionic reaction.