硬质因子对性胺聚合物的影响
Chicheung Su1, Russell Hopson, Paul G Williard
1Department of Chemistry, Brown University , 324 Brook Street, Providence, Rhode Island 02912 United States.
Journal of the American Chemical Society
|January 24, 2014
概括
化胺基的固体阻碍决定了它们与n-丁的聚合状态. 较少阻碍的胺形成2:2聚合物,而增加的硬质量有利于2:1混合聚合物,影响溶液结构.
科学领域:
- 有机金属化学 有机金属化学
- 超分子化学 超分子化学
- 核磁共振光谱法 核磁共振光谱法
背景情况:
- 化胺基是不对称合成中的关键中间体.
- 了解它们在溶液中的聚合行为对于控制反应性至关重要.
- 与有机试剂混合的聚合物可以表现出独特的结构和化学特性.
研究的目的:
- 为了研究化胺和n-丁之间形成的混合聚合物的溶液结构.
- 阐明固体阻碍在控制聚合状态中的作用.
- 为了将结构特征与基拉胺胺上替代物的性质相关联.
主要方法:
- 核磁共振 (NMR) 光谱,包括扩散顺序的NMR (DOSY) 与扩散系数-重量公式 (D-FW) 相对应.
- 采用了一维和二维的NMR技术.
- 在烯-d8溶液中的聚合物的表征.
主要成果:
- 混合聚合物的聚合状态是由化胺的R1和R2组的固态阻碍控制的.
- 当R2受到较小阻碍时, (S) -N-异-1-((三) 氧) -2-胺形成2:2梯形混合聚合物与n-丁.
- 增加的固体阻碍促进了2:1混合聚合物的形成,对于最受阻碍的胺,只观察到2:1聚合物.
结论:
- 在这些混合胺-n-丁系统中,绝缘体积是聚合数和结构的主要决定因素.
- 从2:2聚合到2:1聚合的过渡随着固体需求的增加而发生.
- 这些发现提供了关于性有机物种溶液状态自我组装的见解.
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