Scandium-catalyzed polymerization of CH3(CH2)nCH=CH2 (n = 0–4): remarkable activity and tacticity control
Scandium-catalyzed polymerization of CH3(CH2)nCH=CH2 (n = 0–4): remarkable activity and tacticity control
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DOI：
10.1002/ejic.200801106
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发表时间：
2009-03
影响因子：
2.3
通讯作者：
Benjamin D. Ward;Lenka Lukešová;H. Wadepohl;S. Bellemin‐Laponnaz;L. Gade
中科院分区：
文献类型：
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作者：
Benjamin D. Ward;Lenka Lukešová;H. Wadepohl;S. Bellemin‐Laponnaz;L. Gade
当用两当量的 [Ph3C][B(C6F5)4] 活化时，C3 对称三恶唑啉负载的钪络合物 [Sc(iPr-trisox)(CH2SiMe3)3] (2) 在丙烯、1-丁烯、1-戊烯、1-己烯和 1-庚烯的立体定向聚合中具有高活性。由此产生的聚合物被发现具有窄的分子量分布和高水平的立构规整度控制（高达99％mmmm）。通过 1H、13C 和 29Si NMR 实验获得了对活性物质性质的一些了解。特别是，在环境温度下观察到两个当量的 Ph3CCH2SiMe3 的形成以及暂时指定为双阳离子 [Sc(iPr-trisox)- (CH2SiMe3)]2+ 的 C3 对称钪络合物。
The C3-symmetric trisoxazoline-supported scandium complex [Sc(iPr-trisox)(CH2SiMe3)3] (2) is highly active in the stereospecific polymerization of propene, 1-butene, 1-pentene, 1-hexene and 1-heptene, when activated with two equivalents of [Ph3C][B(C6F5)4]. The polymers thus produced were found to possess narrow molecular weight distributions and high levels of tacticity control (up to 99% mmmm). Some insight into the nature of the active species was obtained by 1H, 13C and 29Si NMR experiments. In particular, the formation of two equivalents of Ph3CCH2SiMe3 at ambient temperature was observed alongside a C3-symmetric scandium complex tentatively assigned as the dication [Sc(iPr-trisox)- (CH2SiMe3)]2+.