埃文斯乙酸盐:化氧化二胺衍生乙酸盐的溶液结构
Evan H Tallmadge1, David B Collum1
1Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853-1301, United States.
Journal of the American Chemical Society
|October 6, 2015
概括
乙烯酸盐在溶液中形成复杂的聚合物,如二聚和四聚. 它们的结构取决于特定的oxazolidinone辅助和溶剂条件.
科学领域:
- 有机化学 有机化学
- 频谱学是一种光谱学.
- 计算化学计算化学
背景情况:
- 在非对称的合成中,基于佐利丁的酸盐是关键的中间体.
- 了解它们在溶液中的聚合状态是控制反应性的关键.
- 以前的研究表明各种聚合行为,但详细的结构见解是有限的.
研究的目的:
- 阐明在四水 (THF) 溶液中基于oxazolidinone的乙烯酸盐的聚合状态和结构.
- 调查辅助结构,酸盐替代和溶剂组成对聚合物的影响.
- 提供对这些关键合成中间体的全面了解.
主要方法:
- 核磁共振 (NMR) 光谱,特别是-6 (6Li) 和碳-13 (13C) 的NMR.
- 计算研究,包括密度函数理论 (DFT) 计算.
- 在THF和THF/托卢混合物中进行了可变度研究.
主要成果:
- 观察到二聚体,四聚体和寡聚体 (潜在的梯子) 的混合物.
- 聚合状态分布对佐利丁辅助结构和酸盐替代剂敏感.
- 在未溶解的条件下,四面体呈现出一个D(2d) - 对称的核心.
- 分子被确定为具有多个异构体形式的三酸盐,由实验和计算数据证实.
结论:
- 乙烯酸盐的聚合行为是复杂的,并且高度依赖于分子和环境因素.
- 这些聚合物的详细结构特征可以通过综合光谱和计算方法来实现.
- 这项工作为埃文斯酸盐的溶液状态结构提供了关键的见解,这与立体选择性合成有关.
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