通过N-异环碳素进行质子转移聚合:单体和催化剂范围以及将二甲酸盐转化为不和聚合物的机制
Miao Hong1, Xiaoyan Tang1, Laura Falivene2,3
1Department of Chemistry, Colorado State University , Fort Collins, Colorado 80523-1872, United States.
Journal of the American Chemical Society
|January 19, 2016
概括
通过N-异环碳素 (NHC) 催化质子转移聚合 (HTP) 从二甲酸盐中产生不和聚合物. 这项研究详细介绍了HTP机制,催化剂活性以及具有自我固化的生物质衍生聚.
科学领域:
- 聚合物化学
- 有机合成
- 催化剂
背景情况:
- N-异环碳酸 (NHC) 是有机合成中的多功能催化剂.
- 质子转移聚合 (PTP) 是一种需要蛋白质单体的聚合方法.
- 双甲酸盐 (DMA) 是常见的单体,缺乏蛋白质组,限制了它们在传统的PTP中的使用.
研究的目的:
- 研究N-异环碳素 (NHC) 催化质子转移聚合物 (HTP) 用于将二甲酸盐 (DMA) 转化为不和聚合物.
- 探索这种新型HTP的机制,单体范围和催化剂结构-活性关系.
- 合成和描述新型NHC催化剂及其衍生物.
主要方法:
- 使用NHC催化剂进行各种DMA的试验聚合.
- 合成和NHC催化剂及其衍生物的结构特征.
- 理论/计算调查以阐明HTP机制和催化剂行为.
主要成果:
- 通过NHC催化HTP成功将六种不同的DMA聚合成不和聚合物.
- 一种生物质衍生furfuryl二甲酸基聚的鉴定,该聚具有自我固化能力.
- 结构-活性关系研究显示特定的NHC衍生物 ((OMe2) TPT) 是最活跃的催化剂,产生具有最高分子量的聚合物.
结论:
- 由NHC催化的HTP是一种可行的方法,用于从DMA合成不和聚合物.
- HTP机制涉及通过酶胺中间体,合物添加,质子转移和NHC释放的阶段生长.
- 计算研究支持提出的机制,并根据中间体的热力学稳定性解释观察到的催化剂性能.
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