Nickel complexes based on BIAN ligands: transformation and catalysis on ethylene polymerization

Area of Science:

• Organometallic Chemistry
• Catalysis
• Polymer Science

Background:

• Bis(arylimino)acenaphthene (ArBIAN) ligands are versatile scaffolds in coordination chemistry.
• Nickel complexes are widely studied for their catalytic applications, particularly in olefin polymerization.

Purpose of the Study:

• To synthesize and characterize novel nickel complexes supported by ArBIAN ligands.
• To evaluate the catalytic activity of these complexes in ethylene polymerization.
• To investigate the structural and electronic properties of the synthesized nickel complexes.

Main Methods:

• Synthesis of Ni(0), Ni(I), and Ni(II) complexes using ArBIAN ligands and nickel precursors.
• Characterization by NMR, IR spectroscopy, and X-ray diffraction analysis.
• Evaluation of catalytic performance in ethylene polymerization using AlMe3 as a co-catalyst.

Main Results:

• Successfully synthesized and characterized several ArBIAN-supported nickel complexes, including Ni(0), Ni(I), and Ni(II) species.
• Complex 2b demonstrated high activity in ethylene polymerization when combined with AlMe3.
• The 2b/AlMe3 system produced polymers with lower branching compared to a benchmark catalyst.

Conclusions:

• The novel ArBIAN-supported nickel complexes are effective catalysts for ethylene polymerization.
• The choice of ligand and nickel oxidation state influences catalytic activity and polymer microstructure.
• This study expands the scope of nickel-based catalysts for producing polyolefins with controlled properties.