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内分子键对线性氨基醇的形态灵活性的依赖性
Yuhui Li1, Xinlang Yang2, Yuanqin Yu1
1School of Physics and Optoelectronic Engineering, Anhui University, Hefei 230601, China.
The journal of physical chemistry. A
|October 24, 2023
概括
氨基醇中的分子内键显示链长度依赖. 最强的键在n=4时形成,但n=3在室温下是最佳的,因为,影响药物设计.
科学领域:
- 物理化学 物理化学
- 分子光谱学 分子光谱学
- 计算化学计算化学
背景情况:
- 分子内键 (H键) 在生物和化学过程中至关重要.
- 预测H键的强度是具有挑战性的,因为复杂的结构和硬质因素.
研究的目的:
- 研究脊柱链长度对线性氨基醇中分子内H键形成的影响.
- 阐明控制H键稳定性的热力学和结构因素.
主要方法:
- 光声学拉曼光谱 (PARS) 用于测量氨基醇 (n=2-5) 的气相光谱.
- 量子化学计算 (MP2/aug-cc-pVTZ//M062X/6-311++G(d,p)) 用于光谱分析和热力学数据.
- 剑桥结构数据库 (CSD) 的统计分析,以确定环形形成偏好.
主要成果:
- 在n=2-4的氨基醇中确定了O-H···N分子内H键,但在n=5.5中没有.
- 在n=4时观察到最强的H键红移,在n=3 (六条环) 时在室温下形成最佳的H键.
- 热力学分析揭示了较长链的不利贡献,随着温度的变化,吉布斯自由能量最佳值发生了变化.
结论:
- 链条长度和环形大小显著影响分子内H键的强度和形成.
- 对H键稳定性起着至关重要的作用,特别是在较长的链中.
- 结果为分子层面的理解和药物设计和超分子组装中的应用提供了洞察力.
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