结合聚合物拓学的启动器控制在环开放的基基甲基化聚合物中
Stephen von Kugelgen1, Donatela E Bellone1, Ryan R Cloke1
1Department of Chemistry, University of California , Berkeley, California 94720, United States.
Journal of the American Chemical Society
|April 28, 2016
概括
碳复合体启动环开放的基甲基酶聚合. 终端组中的硬质差异决定了线性或循环合聚合物是否形成.
科学领域:
- 有机金属化学 有机金属化学
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
背景情况:
- 碳复合物是基因转基因的有效催化剂.
- 环开放性基基转化聚合 (ROMP) 能够合成合聚合物.
- 合成具有控制拓的合聚合物是一个重大挑战.
研究的目的:
- 调查启动器结构对ROMP中的聚合物拓学的影响.
- 使用碳复合物合成完全结合的聚 (o-乙烯乙烯) 合成.
- 阐明控制线性与周期性聚合物形成的机制.
主要方法:
- 5,6,11,12-tetradehydrobenzo[a,e][8]annulene的环开基因转基因的聚合.
- 使用含有梅西 (Mes) 或乙烯 (Et) 末端组的碳酸复合体进行启动.
- 动力学研究分析聚合机制.
主要成果:
- 碳化合物复合物成功启动了紧张的循环基的活体ROMP.
- 终端组的硬质体大部分 (Mes vs. ) 确定了聚合物拓结构.
- [MesCMo(OC(CH3)(CF3)2)3] 仅限于产生线性聚 (o-乙烯乙烯).
- [EtCMo(OC(CH3)(CF3)2)3]产生了循环聚合物 (n=5-20).
- 动力学研究表明,在乙烯末端组的情况下,分子内谤.
结论:
- 启动的卡宾连接体的固体性质在控制聚合物拓学中起着至关重要的作用.
- 这项工作展示了一种合成线性和循环合聚合物的方法.
- 这些发现为ROMP的机制和聚合物合成催化剂设计提供了洞察力.
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