Preparation of Phosphine-Amido Hafnium and Zirconium Complexes for Olefin Polymerization

详细信息    查看全文

• 作者：Sung Hae Jun ; Ji Hae Park ; Chun Sun Lee ; Seong Yeon Park ; Min Jeong Go ; Junseong Lee ; Bun Yeoul Lee
• 刊名：Organometallics
• 出版年：2013
• 出版时间：December 23, 2013
• 年：2013
• 卷：32
• 期：24
• 页码：7357-7365
• 全文大小：321K
• ISSN：1520-6041

文摘

Aniline (N-R-C₆H₅NH) and 1,2,3,4-tetrahydroquinoline (2-R-C₉H₉NH) derivatives were ortho-lithiated via conversion of the respective 鈭扤H groups to 鈭扤(COOLi), followed by treatment with tBuLi. The resulting ortho-lithiated compounds were transformed to ortho-Ph₂P-substituted derivatives on treatment with Ph₂P(OPh). Further reaction of the resulting compounds with M(CH₂Ph)₄ (M = Zr, Hf) afforded a series of Hf and Zr complexes: (2-R-8-Ph₂PC₉H₉N)Hf(CH₂Ph)₃ (8, R = H; 9, R = Me; 10, R = iPr; 11, R = nBu), (N-R-2-Ph₂PC₆H₄N)Hf(CH₂Ph)₃ (12, R = Me; 13, R = Et; 14, R = iPr), (2-R-8-Ph₂PC₉H₉N)Zr(CH₂Ph)₃ (15, R = H; 16, R = Me; 17, R = iPr; 18, R = nBu), and (N-R-2-Ph₂PC₆H₄N)Zr(CH₂Ph)₃ (19, R = Me; 20, R = Et)]. X-ray crystallographic studies of 9, 14, 16, and 19 revealed a distorted trigonal-bipyramidal structure with two benzyl moieties in equatorial positions and the remaining benzyl ligand occupying an apical position; in solution, however, three benzyl ligands became scrambled, as evidenced by a single set of benzyl signals in the corresponding ¹H NMR spectra. The complexes showed comparable activities (17鈥?8 脳 10⁶ g/mol-M路h) to the Ti-based constrained geometry catalyst (CGC) (36 脳 10⁶ g/mol-Ti路h) in ethylene/1-octene copolymerization, despite their inferior 1-octene incorporation capabilities (3鈥? mol % versus 17 mol %). Compound 15 showed a moderate 1-octene incorporation capability (7.7 mol %), whereas the others showed low 1-octene incorporations (2鈥? mol %). Compounds 9 and 16 provided high-molecular-weight polymers with M_w > 200鈥?00 even at high reaction temperatures of 100鈥?30 掳C.