用第二代霍维达-格鲁布斯催化剂进行环开转化聚合:一种高纯度功能化宏环氧烯的高效方法
1Polymer Science Group, Department of Chemical and Biomolecular Engineering, The University of Melbourne, Parkville, Melbourne, Victoria 3010, Australia.
Journal of the American Chemical Society
|March 27, 2013
概括
这项研究引入了一种新方法,用于使用环开放型转化聚合制造纯粹的,功能性的宏环氧烯. 这种方法确保了高产量和纯度,避免了各种应用的线性副产品.
科学领域:
- 聚合物化学 聚合物化学
- 有机合成 有机合成
- 宏分子科学 宏分子科学
背景情况:
- 宏环聚合物提供独特的特性,但具有高纯度的合成具有挑战性.
- 环开元化聚合 (ROMP) 是聚合物合成的一个强大的工具.
- 控制聚合物架构,特别是宏循环,仍然是积极研究的领域.
研究的目的:
- 为制备功能化宏环氧酸 (cOCOEs) 制定一个简单的和通用的策略.
- 在使用ROMP的宏循环合成中实现高纯度和高产量.
- 研究特定催化剂在控制宏环化与线性聚合过程中的作用.
主要方法:
- 使用环开放型转化聚合物 (ROMP) 与分子内反.
- 采用第二代Hoveyda-Grubbs (HG2) 催化剂,用于聚合环洛烯衍生物.
- 应用的异化物衍生物用于有效的催化剂火和去除.
- 使用GPC,NMR,元素分析,GPC-MALDI ToF MS和ICP-AES的产品进行了特征化.
主要成果:
- 实现了高产量 (95%) 的宏环性基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基 (cOACOE) 具有受控的分子量 (1.6 kDa) 和低多分散性 (1.6).
- 证实了没有可检测的末端组的宏循环结构的排他性形成.
- 成功地将该方法扩展到其他环烯单体,产生了多种功能化的COCOEs.
- 证明HG2催化剂,特别是其双基基联体,对于选择性宏循环化至关重要,与其他格鲁布斯催化剂不同.
结论:
- 提出的策略提供了一个强大的和一般的方法,用于合成高纯度的功能化宏环氧氧化物 (cyclooctene).
- 霍维达-格拉布斯催化剂在指导ROMP向分子内反转和宏循环形成方面发挥着关键作用.
- 这项工作为访问具有材料科学潜在应用的新型宏观循环架构打开了道路.
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