A series of 2-(2-benzhydrylbenzenamino)pyridine ligands (L1–L13) was synthesized and used as bidentate N^N ligands with nickel halides to afford the corresponding nickel dihalide complexes L2Ni2Cl4C1–C13 and L2NiBr2D1–D13. All ligands and complexes were characterized by IR and NMR spectroscopy, and by elemental analysis. The molecular structures of the representative complexes C1·2CH3OH, C5·2H2O, D4, D7 and D9 were confirmed by single-crystal X-ray diffraction studies. Upon activation with either methylaluminoxane (MAO) or ethylaluminium sesquichloride (Et3Al2Cl3, EASC), these nickel pre-catalysts exhibited high activities (up to the range of 107 g mol−1 (Ni) h−1) towards ethylene polymerization, producing branched polyethylenes with narrow polydispersity.
合成了一系列 2-(2-二苯甲基苯
氨基)
吡啶配体(L1-L13),并将其作为与卤化
镍的双齿 N^N
配体,得到了相应的二卤化
镍配合物
L2Ni2Cl4C1-C13 和
L2NiBr2D1-D13。所有
配体和配合物都通过红外光谱、核磁共振光谱和元素分析进行了表征。代表性配合物 C1-2CH3OH、C5-2H2O、
D4、D7 和 D9 的分子结构已通过单晶 X 射线衍射研究得到证实。在甲基铝氧烷(MAO)或乙基
三氯化铝(Et3A
L2Cl3,EASC)的活化下,这些
镍前催化剂在
乙烯聚合方面表现出很高的活性(高达 107 g mol-1 (Ni) h-1 的范围),生成的支链聚
乙烯具有很窄的聚分散性。