伪烯衍生的迈尔斯乙酸盐:化对反应性和机制的结构和影响
Yuhui Zhou1, Janis Jermaks1, Ivan Keresztes1
1Department of Chemistry and Chemical Biology, Baker Laboratory , Cornell University , Ithaca , New York 14853-1301 , United States.
Journal of the American Chemical Society
|March 22, 2019
概括
伪埃弗德林衍生的二乙烯酸盐形成复杂的四相和三相. 这些聚合物表现出独特的结构和反应性,化添加物加速化反应.
科学领域:
- 有机化学 有机化学
- 有机金属化学 有机金属化学
- 超分子化学 超分子化学
背景情况:
- 了解埃诺酸盐的聚合行为对于控制有机合成中的反应性至关重要.
- 伪乙烯衍生的酸盐为不对称合成提供了合性支架.
- 胺基如二胺基 (LDA) 在化物化学中被广泛使用.
研究的目的:
- 为了阐明伪埃弗德林衍生的二基迈尔斯乙醇酸的结构和聚合状态.
- 调查化对酸盐聚合和反应性的影响.
- 了解涉及这些乙烯酸盐的化反应的动力学因素.
主要方法:
- 核磁共振 (NMR) 光谱学 核磁共振 (NMR) 光谱学
- 红外 (IR) 光谱法 红外 (IR) 光谱法 红外 (IR) 光谱法
- 在X射线晶体学.
- 计算建模 (DFT) 的使用
- 同位素标签研究的研究.
- 连续变化的方法.
- 动力学研究 (化反应)
主要成果:
- 迪亚尼乙烯酸盐形成八化四聚体,具有S4对称的Li8O8核和C2对称.
- 强烈的N-Li接触被观察到在碳胺乙烯酸盐部分.
- 酸盐和LDA的混合聚合物形成了六合化trimers.
- 化形成了具有未知的结构的 adducts,这极大地加快了化.
- 聚合老化显著影响反应速率,覆盖数量级.
结论:
- 伪乙烯衍生的酸盐的聚合状态复杂且对反应条件敏感.
- 化在调节酸盐反应性方面发挥着重要作用,尽管需要超级化量.
- 需要进一步的研究,以优化LiCl添加物的使用,以实现高效的合成,并了解自身抑制机制.
相关概念视频
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