An alpha-Diimine-Nickel(II) catalyst bearing an electron-withdrawing substituent for olefin polymerization

作者：Yuan Jianchao^*; Wang Xuehu; Mei Tongjian; Liu Yufeng; Miao Chengping; Xie Xiaoli

来源：Transition Metal Chemistry, 2011, 36(4): 433-439.

DOI：10.1007/s11243-011-9487-x

A Br-substituted alpha-diimine ligand, bis[N,N'(4-bromo-2,6-dimethylphenyl)imino]-2,3-butadiene L1, and its corresponding Ni(II) complex, {bis[N,N'-(4-bromo-2,6-dimethylphenyl) imino]-2,3-butadiene} dibromonicke [NiBr(2)(L1)], have been synthesized and characterized. The crystal structure of the free ligand (L1) was determined by X-ray crystallography. Two alpha-diimine-Ni(II) catalysts, {bis[N,N'-(2,4,6-dimethylphenyl)imino]-2,3-butanedione} dibromonickel[NiBr(2)(L2)] and {bis[N,N'-(2,6-dimethylphenyl) imino]-2,3-butanedione} dibromonickel [NiBr(2)(L3)], were also synthesized and characterized for comparison. The complex [NiBr2(L1)], when activated by diethylaluminum chloride, produces the most active catalytic system for the polymerization of ethylene among the three complexes. NMR analysis shows that the degree of branching of polyethylene increases in the presence of electron-withdrawing groups under the same reaction conditions.

• 出版日期2011-5
• 单位西北师范大学