Synthesis and characterization of N-(2-pyridyl)benzamide-based nickel complexes and their activity for ethylene oligomerization |
| |
Authors: | Wen-Hua Sun Wen Zhang Xiubo Tang Yan Li |
| |
Affiliation: | a State Key Laboratory of Engineering Plastics and The Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun, Beiyijie, Beijing 100080, China b Institute of Physical Chemistry, Peking University, Beijing 100871, China |
| |
Abstract: | A series of N-(2-pyridyl)benzamides (1)-(11) and their nickel complexes, [N-(2-pyridyl)benzamide]dinickel(II) di-μ-bromide dibromide (12)-(16) and (aryl)[N-(2-pyridyl)benzamido](triphenylphosphine)nickel(II) (17)-(24), were synthesized and characterized. The single-crystal X-ray analysis revealed that 12 and 14 are binuclear nickel complexes bridged by bromine atoms and each nickel atom adopts a distorted trigonal bipyramidal geometry. The key feature of the complexes 17, 19 and 23 is each has a six-membered nickel chelate ring including a deprotonated secondary nitrogen atom and an O-donor atom. The nickel complexes show moderate to high catalytic activity for ethylene oligomerization with methylaluminoxane (MAO) as cocatalyst. The activity of 12-16/MAO systems is up to 3.3 × 104 g mol−1 h−1 whereas for 17-24/MAO systems it is up to 4.94 × 105 g mol−1 atm−1 h−1. The influence of Al/Ni molar ratio, reaction temperature, reaction period and PPh3/Ni molar ratio on catalytic activity was investigated. |
| |
Keywords: | N-(2-Pyridyl)benzamide ligand Nickel complexes Crystal structures Ethylene oligomerization |
本文献已被 ScienceDirect 等数据库收录! |
|