Synthesis, Structure, and Olefin Polymerization Behavior of Constrained-Geometry Group 4 Metallacarboranes Incorporating Imido-Dicarbollyl Ligands
详细信息 查看全文
- 作者：Mingli Gao ; Yong Tang ; Meihua Xie ; Changtao Qian ; and Zuowei Xie
- 刊名：Organometallics
- 出版年：2006
- 出版时间：May 8, 2006
- 年：2006
- 卷：25
- 期：10
- 页码：2578 - 2584
- 全文大小：157K
- 年卷期：v.25,no.10(May 8, 2006)
- ISSN：1520-6041
文摘
New imido-carboranes 1-(CH=NC6H3R2-2,6)-1,2-C2B10H11 (R = iPr (3a), Me (3b)) were successfullyprepared by Schiff base condensation of 1-CHO-1,2-C2B10H11 with R2C6H3NH2. They were readilyconverted into the corresponding imido-dicarbollyl ligands 7-(CH=NHC6H3R2-2,6)-7,8-C2B9H11 (R =iPr (4a), Me (4b)) by refluxing in dry MeOH. Treatment of 3a with Ti(NMe2)4 in hot toluene gave aconstrained-geometry complex, [
1:5-(iPr2C6H3N=CH)C2B9H10]Ti(NMe2)2 (5a). Under the same reactionconditions, interaction of 3b with Ti(NMe2)4 produced a mixture of [1:5-(Me2C6H3N=CH)C2B9H10]Ti(NMe2)2 (5b) and [1:5-(Me2N)CH(NMe2)(C2B9H10)Ti(NMe2)2 (8). Reaction of 4a with M(NMe2)4in toluene/DME at room temperature afforded 5a and [1:5-(iPr2C6H3N=CH)C2B9H10]M(NMe2)2(NHMe2)(M = Zr (6a), Hf (7a)), respectively. Complexes 5a, 6a, and 7a were active catalysts for the polymerizationof ethylene in the presence of MMAO with activities of 3-16 kg/mol·h·atm. These new complexeswere fully characterized by various spectroscopic techniques and elemental analyses. The molecularstructures of 3a, 3b, 4a, 5a, 5b, 6a, 7a, and 8 were further confirmed by single-crystal X-ray analyses.
1:5-(iPr2C6H3N=CH)C2B9H10]Ti(NMe2)2 (5a). Under the same reactionconditions, interaction of 3b with Ti(NMe2)4 produced a mixture of [1:5-(Me2C6H3N=CH)C2B9H10]Ti(NMe2)2 (5b) and [1:5-(Me2N)CH(NMe2)(C2B9H10)Ti(NMe2)2 (8). Reaction of 4a with M(NMe2)4in toluene/DME at room temperature afforded 5a and [1:5-(iPr2C6H3N=CH)C2B9H10]M(NMe2)2(NHMe2)(M = Zr (6a), Hf (7a)), respectively. Complexes 5a, 6a, and 7a were active catalysts for the polymerizationof ethylene in the presence of MMAO with activities of 3-16 kg/mol·h·atm. These new complexeswere fully characterized by various spectroscopic techniques and elemental analyses. The molecularstructures of 3a, 3b, 4a, 5a, 5b, 6a, 7a, and 8 were further confirmed by single-crystal X-ray analyses.