Three mono-cyclopentadienyl metal complexes, [C_6H_4O_2]CpTiCl (Ⅰ),[C_(12)H_8O_2]CpTiCl (Ⅱ), and [C_(20)H_(12)O_2] CpTiCl (Ⅲ), were prepared via the reactions ofcyclopentadienyl titanium trichloride with catechol, ...Three mono-cyclopentadienyl metal complexes, [C_6H_4O_2]CpTiCl (Ⅰ),[C_(12)H_8O_2]CpTiCl (Ⅱ), and [C_(20)H_(12)O_2] CpTiCl (Ⅲ), were prepared via the reactions ofcyclopentadienyl titanium trichloride with catechol, 2,2i-bisphenol, and 2,2'-bisnaphthol,respectively. In the presence of a moderate amount of methylaluminoxane (MAO), the complexesexhibited catalytic activities for ethylene polymerization. Complex Ⅰ showed the highest activityat Al/Ti molar ratio of 500 at the temperature of 30℃. With increasing of polymerizationtemperature, catalytic activities and molecular weight of the obtained polyethylene tended todecrease, and molecular weight distribution of polyethylene became narrower. With the molecularsimulation method, the charges on titanium atoms of complexes Ⅰ, Ⅱ, and Ⅲ, and the bond anglesformed by Ti and bisphenoxy ligands were calculated. It was concluded that the smaller the netcharge on Ti and the smaller the angle of O1―Ti―O2, the higher the activity of the complex.展开更多
C_6H_5CH_2C_5H_4ErCl_2(THF)_3]·THF, Mr=681.9, monoclinic,space group P2_1/n, with a=11. 622(5), b=10. 281(4), c=26. 040(5),β=86. 65 (4)°,V=3106 (3), Z=4, Dc=1. 46 gcm￣(-3),μ=30. 0 cm￣(-1), F (000)=1380. ...C_6H_5CH_2C_5H_4ErCl_2(THF)_3]·THF, Mr=681.9, monoclinic,space group P2_1/n, with a=11. 622(5), b=10. 281(4), c=26. 040(5),β=86. 65 (4)°,V=3106 (3), Z=4, Dc=1. 46 gcm￣(-3),μ=30. 0 cm￣(-1), F (000)=1380. The final R value is 0. 040 for 1911 independent observed reflections (I>3σ(I)). The geometry around the erbium ion is described as an approximate octahedron with the centroid of the benzylcyclopentadienyl rings, the oxygens of three THF's and two chlorine atoms forming the apices of the octahedron. The average distance of Er-C(Cp'ring) is 2. 66A.展开更多
基金The work is supported by Special Funds for State Major Basic Research Projects of China(No.G1999064801)
文摘Three mono-cyclopentadienyl metal complexes, [C_6H_4O_2]CpTiCl (Ⅰ),[C_(12)H_8O_2]CpTiCl (Ⅱ), and [C_(20)H_(12)O_2] CpTiCl (Ⅲ), were prepared via the reactions ofcyclopentadienyl titanium trichloride with catechol, 2,2i-bisphenol, and 2,2'-bisnaphthol,respectively. In the presence of a moderate amount of methylaluminoxane (MAO), the complexesexhibited catalytic activities for ethylene polymerization. Complex Ⅰ showed the highest activityat Al/Ti molar ratio of 500 at the temperature of 30℃. With increasing of polymerizationtemperature, catalytic activities and molecular weight of the obtained polyethylene tended todecrease, and molecular weight distribution of polyethylene became narrower. With the molecularsimulation method, the charges on titanium atoms of complexes Ⅰ, Ⅱ, and Ⅲ, and the bond anglesformed by Ti and bisphenoxy ligands were calculated. It was concluded that the smaller the netcharge on Ti and the smaller the angle of O1―Ti―O2, the higher the activity of the complex.
文摘C_6H_5CH_2C_5H_4ErCl_2(THF)_3]·THF, Mr=681.9, monoclinic,space group P2_1/n, with a=11. 622(5), b=10. 281(4), c=26. 040(5),β=86. 65 (4)°,V=3106 (3), Z=4, Dc=1. 46 gcm￣(-3),μ=30. 0 cm￣(-1), F (000)=1380. The final R value is 0. 040 for 1911 independent observed reflections (I>3σ(I)). The geometry around the erbium ion is described as an approximate octahedron with the centroid of the benzylcyclopentadienyl rings, the oxygens of three THF's and two chlorine atoms forming the apices of the octahedron. The average distance of Er-C(Cp'ring) is 2. 66A.
