Phosphinobenzenamine Nickel Catalyzed Efficient Copolymerization of Methyl Acrylate with Ethylene and Norbornene

Abstract

A series of phosphinobenzenamine-based nickel complexes bearing substituted phenylphosphine ligands were synthesized and characterized. These nickel complexes combined with methylaluminoxane (MAO) exhibited very high activity (∼10 6 g mol −1 h −1 ) and good thermal stability for norbornene polymerization. The nickel catalysts were able to conduct copolymerization of norbornene and methyl acrylate (MA) with high activity (3.76 × 10 5 g mol −1 h −1 ) to give high-molecularweight functionalized cyclic olefin copolymer (COC) with reasonable MA incorporation (2.39−6.47 mol %). Moreover, the nickel catalysts also promote the copolymerization of ethylene and MA with moderate activity (∼10 4 g mol −1 h −1 ) to produce semicrystalline high-molecular-weight polar functionalized polyethylene (PE). The MA incorporation in the copolymer was controlled in a wide range (up to 15.5 mol %). These complexes without any sterically bulky substituent on the ligand are distinctive examples of earth-abundant nickel complexes toward the direct copolymerization of ethylene or norbornene with the challenging vinyl polar monomer MA.

A cavity-shaped cis-chelating P,N ligand for highly selective nickel-catalysed ethylene dimerisation

“…44,45 Many studies have focused on varying the electronic properties of both Pand N-donor atoms, but steric factors have also been found to play a crucial role in the metal-catalysed oligomerisation of ethylene to α-olefins. 46,54 In particular, the presence of steric bulk at the metal axial sites tends to inhibit termination reactions, thus favouring chain growth. 47 The cavity-shaped complex 9 exhibits a unique steric environment, in which the phosphorus atom is heavily congested and forces the chelated metal to be encapsulated in the CD with both axial sites protected by CD 6-methoxy groups.…”

Synthesis and Characterization of Phosphinobenzenamine Palladium Complexes and Their Application in Ethylene Polymerization and Copolymerization with Polar Monomers

“…Phosphinobenzenamine ligands L1 – L5 were synthesized following the procedure in our recently published study . Expected palladium complexes Pd1 – Pd5 were obtained in good yields (80%–95%) by treating each ligand with the palladium precursor (PdClMe­(COD)) (Scheme ).…”

“…Therefore, the rational design of a ligand structure can be considered as a straightforward pathway toward improving the catalytic performances of N ∧ P-based palladium complexes. Recently, we have synthesized a series of novel N ∧ P-type phosphinobenzenamine nickel catalysts and conducted efficient olefin polymerization and copolymerization with polar monomers . Here we report the synthesis of phosphinobenzenamine-ligated palladium complexes and their catalytic behaviors toward ethylene (co)­polymerization with polar monomers.…”

“…Recently, we have synthesized a series of novel N ∧ P-type phosphinobenzenamine nickel catalysts and con- ducted efficient olefin polymerization and copolymerization with polar monomers. 38 Here we report the synthesis of phosphinobenzenamine-ligated palladium complexes and their catalytic behaviors toward ethylene (co)polymerization with polar monomers.…”

Influence of Silica-Supported Alkylaluminum on Heterogeneous Zwitterionic Anilinonaphthoquinone Nickel and Palladium-Catalyzed Ethylene Polymerization and Copolymerization with Polar Monomers

“…Polyolefins are a family of widely used polymeric materials with rapid development and huge production in the current plastics industry. − The introduction of a very small amount of polar functional groups on the nonpolar polyolefin backbone can significantly improve the properties of polyolefins, and it is highly challenging to achieve such functionalized materials through the direct coordination copolymerization of olefin and polar monomers . Palladium- and nickel-based late transition metal catalysts have developed rapidly in recent years due to their lower electrophilicity compared with early transition metal catalysts and thus have gained superiority in catalyzing the direct copolymerization of olefin and polar monomers to produce functional polyolefins. − However, it is rather difficult to achieve the industrial production of functional polyolefins using homogeneous late transition metal catalysts due to some serious shortcomings, such as uncontrolled polymer morphology and serious reactor fouling. The heterogenization of homogeneous late transition metal catalysts has been considered as a promising pathway to overcome the above problems. − …”