用NMR和计算分析对二醇-酸复合物的形成进行动力学和热力学研究
Brandy L Davidson1, Elaina Manyin1, Nathan E Morris1
1Department of Chemistry and Biochemistry, James Madison University, Harrisonburg, Virginia 22807, United States.
ACS omega
|December 1, 2025
概括
酸与有机溶剂中的二醇形成复合物,其中1,3-二醇最稳定,1,2-二醇在动力学上更受青. 这项研究使用光谱学和理论来探索这些复合体.
科学领域:
- 超分子化学 超分子化学
- 有机化学 有机化学
- 计算化学计算化学
背景情况:
- 酸 (BA) 与二醇形成可逆的共价B-O键,对于药物输送,材料科学和聚合物化学的应用至关重要.
- 虽然BA-二醇复合在水溶液中是可以理解的,但其在有机溶剂中的行为在很大程度上仍未被探索.
- 了解有机介质中的这些复杂物对于扩大它们的应用至关重要.
研究的目的:
- 研究有机溶剂中中性玻尿酸-二醇复合物的形成和特性,特别是DMSO.
- 通过光谱和理论方法阐明这些复合物的结构和能量特性.
- 评估动力学方面和水对酸-二醇复合物的影响.
主要方法:
- 核磁共振 (NMR) 光谱学被用来研究酸与乙烯基醇 (EG),1,3-二醇 (PD) 和1,4-二醇 (BD) 的复合.
- 使用计算方法来支持实验发现,并计算复杂形成的吉布斯自由能量 (ΔG).
- 通过NMR的动态分析确定了反应速率和水对复合体稳定性的影响.
主要成果:
- 1,3-二醇 (PD) 与BA形成了最稳定的,封闭的B-O复合体,而乙烯基醇 (EG) 则形成了开放和封闭物种的混合物.
- 1,4-butanediol (BD) 显示出有限的复合物形成,主要是开放的二醇-BA复合物,计算结果表明开放/关闭形式的能量相似,可能是由于动力沉降.
- 动力学分析显示了EG-BA,PD-BA和BD-BA复合体具有不同的速率常数的第一阶反应;封闭的1,3-二醇-BA复合体在热力学上受到青,而1,2-二醇-BA复合体在动力学上受到青和动态.
结论:
- 该研究阐明了DMSO中各种二醇与酸的不同复杂化行为,突出了1,3-二醇的热力学稳定性和1,2-二醇的动力学优势.
- 计算分析,包括糖醇-BA复合体中分子内结合的效果,支持实验观测,并提供了对复杂稳定性的更深入的见解.
- 这些发现促进了对有机溶剂中酸化学的理解,为材料和化学合成中量身定制的应用铺平了道路.
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