文献类型：期刊文献

英文题名：Nickel complexes supported by a new class of fused imidazonaphthyridine tridentate N,N,N-ligands for ethylene oligomerization and isolation of a key Ni-Al intermediate

作者：Zuo, Jing;Li, Hongxiu;Hu, Chaojie;Zhao, Mei-Xin[1];Zhang, Jun[1]

机构：[1]East China Univ Sci & Technol, Sch Chem & Mol Engn, Key Lab Adv Mat, 130 Mei Long Rd, Shanghai 200237, Peoples R China; East China Univ Sci & Technol, Inst Fine Chem, Sch Chem & Mol Engn, 130 Mei Long Rd, Shanghai 200237, Peoples R China

年份：2026

外文期刊名：DALTON TRANSACTIONS

收录：;WOS:【SCI-EXPANDED(收录号:WOS:001783580000001)】；

基金：Financial support from the Fundamental Research Funds for the Central Universities (222201717003) and the National Natural Science Foundation of China (22071055) is greatly acknowledged.

语种：英文

摘要：A series of 9-imino-imidazo[1,2-h][1,7]naphthyridine ligands and their nickel complexes were synthesized and structurally characterized by single-crystal X-ray crystallography. X-ray diffraction analysis revealed that 9-imino-imidazo[1,2-h][1,7]naphthyridines were used as tridentate ligands in most cases. Nickel complex Ni2 has a five-coordinate distorted square pyramidal geometry, in which the nickel is coordinated with three nitrogen atoms of the 9-imino-imidazo[1,2-h][1,7]naphthyridine ligand and two chlorines. Nickel complexes Ni1, Ni3 and Ni5 displayed a six-coordinate distorted octahedral geometry upon coordination with a solvent molecule. Upon activation with diethylaluminum chloride (Et2AlCl), high catalytic activity up to 1.20 & times; 107 g mol-1(Ni) h-1 and high selectivity for butenes (95.9%) and 1-butene (99.0%) could be achieved using Ni1 as a catalyst. A higher activity of up to 2.06 & times; 108 g mol-1(Ni) h-1 was observed in the Ni1/Et2AlCl system with the addition of 10 equiv. of PPh3 as an auxiliary ligand. Isolation and structural characterization of a key Ni-Al intermediate provided crystallographic evidence of the role of a co-catalyst in the activation of the Ni precatalyst.