A series of half-sandwich group IV metal complexes with tridentate monoanionic phenoxy-imine arylsulfide [O-NS] ligand [2-Bu^t4-Me-6-（（2-（SC6H5）C6H4N = CHC6H2O）]- （La） and dianionic phenoxy-amine arylsulfide [O...A series of half-sandwich group IV metal complexes with tridentate monoanionic phenoxy-imine arylsulfide [O-NS] ligand [2-Bu^t4-Me-6-（（2-（SC6H5）C6H4N = CHC6H2O）]- （La） and dianionic phenoxy-amine arylsulfide [O-N-S] ligand [2-Bu^t4-Me-6-（（2-（SC6H5）C6H4N-CH2C6H2O）]2- （Lb） have been synthesized and characterized. Lb was obtained easily in high yield by reduction of ligand La with excess LiAlH4 in cool diethyl ether. Half-sandwich Group Ⅳ metal complexes CpTi[O-NS]Cl2 （1a）, CpZr[O-NS]Cl2 （1b）, CpTi[O-N-S]Cl （2a）, CpZr[O-N-S]Cl （2b） and CpZr[O-N-S]Cl （2c） were synthesized by the reactions of La and Lb with CpTiCl3, CpZrCl3 and Cp ZrCl3, and characterized by IR, ^1H-NMR, ^13C-NMR and elemental analysis. In addition, an X-ray structure analysis was performed on ligand Lb. The title Group IV half-sandwich bearing tridentate [O,N,S] ligands show good catalytic activities for ethylene polymerization in the presence of methylaluminoxane （MAO） as co-catalyst up to 1.58 × 10^7 g-PE.mol-Zr-1.h-1. The good catalytic activities can be maintained even at high temperatures such as 100 ℃ exhibiting the excellent thermal stability for these half-sandwich metal pre-catalysts.展开更多
This contribution reports ethylene polymerization behavior of titanium complexes incorporating bis（phenoxyimine） ligands. Six phenoxy-imine Ti（IV） complexes {6-R^1-2-[CH=N（2,6-difluoro-3,5-diR^2-4-R^3Ph）]C6H30}2...This contribution reports ethylene polymerization behavior of titanium complexes incorporating bis（phenoxyimine） ligands. Six phenoxy-imine Ti（IV） complexes {6-R^1-2-[CH=N（2,6-difluoro-3,5-diR^2-4-R^3Ph）]C6H30}2TiCl2 （1： R^1 = H, R^2 = H, R^3 = H; 2： R^1 = H, R^2 = H, R%3 = 4-vinylphenyl; 3： R^1 = CH3, R^2 = H, R^3 = H; 4： R^1 = CH3, R^2 = H, R^3 = 4-vinylphenyl; 5： R^1 = CH3, R^2 = F, R^3 = H; 6： R^1 = CH3, R^2 = F, R^3 = 4-vinylphenyl） have been synthesized and evaluated for ethylene polymerization using dried MAO （simplified as DMAO） as cocatalyst. An obvious catalytic heterogeneity of Cat 2 （Complex 2/DMAO） towards ethylene polymerization was observed, which was illustrated by decreased activity, multi- modal molecular weight distribution and partially improved particle morphology comparing with Cat 1. Moreover, Cat 3 exhibits ＂living＂ characteristics in the process under certain conditions （25 ~C, less than 20 min）. Otherwise, the moderate to high ethylene polymerization activity of ca. 105-106 g PE/（mol Ti＇h） and high molecular weight （Mw = 105-106） of polyethylene can be obtained by changing the skeleton structure of these complexes.展开更多
基金financially supported by the Shanghai Science and Technology Committee(08DZ2270500,08DJ1400103)Shanghai Leading Academic Discipline Project(B108)the National Basic Research Program of China(2009CB825300,2010DFA41160)
文摘A series of half-sandwich group IV metal complexes with tridentate monoanionic phenoxy-imine arylsulfide [O-NS] ligand [2-Bu^t4-Me-6-（（2-（SC6H5）C6H4N = CHC6H2O）]- （La） and dianionic phenoxy-amine arylsulfide [O-N-S] ligand [2-Bu^t4-Me-6-（（2-（SC6H5）C6H4N-CH2C6H2O）]2- （Lb） have been synthesized and characterized. Lb was obtained easily in high yield by reduction of ligand La with excess LiAlH4 in cool diethyl ether. Half-sandwich Group Ⅳ metal complexes CpTi[O-NS]Cl2 （1a）, CpZr[O-NS]Cl2 （1b）, CpTi[O-N-S]Cl （2a）, CpZr[O-N-S]Cl （2b） and CpZr[O-N-S]Cl （2c） were synthesized by the reactions of La and Lb with CpTiCl3, CpZrCl3 and Cp ZrCl3, and characterized by IR, ^1H-NMR, ^13C-NMR and elemental analysis. In addition, an X-ray structure analysis was performed on ligand Lb. The title Group IV half-sandwich bearing tridentate [O,N,S] ligands show good catalytic activities for ethylene polymerization in the presence of methylaluminoxane （MAO） as co-catalyst up to 1.58 × 10^7 g-PE.mol-Zr-1.h-1. The good catalytic activities can be maintained even at high temperatures such as 100 ℃ exhibiting the excellent thermal stability for these half-sandwich metal pre-catalysts.
基金financially supported by the National Natural Science Foundation of China(Nos.20936006 and 20976152)National Basic Research Program of China(2011CB606001)+1 种基金Doctoral Program of Higher Education of China(No.20100101110041)Program for Changjiang Scholars and Innovative Research Team in Zhejiang University
文摘This contribution reports ethylene polymerization behavior of titanium complexes incorporating bis（phenoxyimine） ligands. Six phenoxy-imine Ti（IV） complexes {6-R^1-2-[CH=N（2,6-difluoro-3,5-diR^2-4-R^3Ph）]C6H30}2TiCl2 （1： R^1 = H, R^2 = H, R^3 = H; 2： R^1 = H, R^2 = H, R%3 = 4-vinylphenyl; 3： R^1 = CH3, R^2 = H, R^3 = H; 4： R^1 = CH3, R^2 = H, R^3 = 4-vinylphenyl; 5： R^1 = CH3, R^2 = F, R^3 = H; 6： R^1 = CH3, R^2 = F, R^3 = 4-vinylphenyl） have been synthesized and evaluated for ethylene polymerization using dried MAO （simplified as DMAO） as cocatalyst. An obvious catalytic heterogeneity of Cat 2 （Complex 2/DMAO） towards ethylene polymerization was observed, which was illustrated by decreased activity, multi- modal molecular weight distribution and partially improved particle morphology comparing with Cat 1. Moreover, Cat 3 exhibits ＂living＂ characteristics in the process under certain conditions （25 ~C, less than 20 min）. Otherwise, the moderate to high ethylene polymerization activity of ca. 105-106 g PE/（mol Ti＇h） and high molecular weight （Mw = 105-106） of polyethylene can be obtained by changing the skeleton structure of these complexes.
