氨基和以太化酸试剂-结构和动态.
Hans J Reich1, Wayne S Goldenberg, Aaron W Sanders
1Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, USA. reich@chem.wisc.edu
Journal of the American Chemical Society
|March 20, 2003
概括
在基试剂中的化作用会影响聚合. 以太合物与THF竞争,而氨基合物显示有限的相互作用,导致显著的二分体形成和特定的结构见解.
科学领域:
- 有机金属化学 有机金属化学
- 有机合成 有机合成
- 频谱学是一种光谱学.
背景情况:
- 乙试剂在有机合成中至关重要.
- 了解它们的聚合状态是控制反应性的关键.
- 使用整形替代剂进行化可以显著改变试剂的行为.
研究的目的:
- 调查胺和以太替代物的合胺和以太替代物的对烯聚合物的影响.
- 用先进的光谱技术阐明化作用的结构后果.
- 为了比较不同环形大小和异构原子 (N与O) 的化能力.
主要方法:
- 可变温度6Li和13C核磁共振 (NMR) 光谱学.
- 6Li和15N同位素的标记研究.
- 研究溶剂添加剂的作用,包括四氨酸 (THF) 和1,1,4,7,10-甲基二乙烯胺 (PMDTA).
主要成果:
- 5环和6环以太酸盐 (化合物4,5) 与THF有效竞争.
- 六环胺基酸盐 (化合物2) 与THF竞争较弱,而七环胺基酸盐 (化合物3) 与THF没有竞争.
- 与模型化合物相比,化烯酸试剂表现出显著增强的二分化,因子范围从40到超过20万.
- 通过在同位素标记化合物中的NMR合,为2-(2-dimethylaminoethyl) phenyllithium (2) 分配了一个特定的A型二元体结构.
- 化合物2单体没有可检测的化,而其二元体则表现出化.
- 2 - 甲基 (甲基) (4) 形成一个开放的二元体和一个五坐标的单元体.
- 大多数试剂与PMDTA一起形成单体,非化添加物.
结论:
- 整形替代剂的化强烈促进了烯试剂中的二分化.
- 替代剂在与THF竞争中比氨基替代剂更有效的化剂.
- 合二元的特定结构赋值是可能的,为聚合行为提供了洞察力.
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