在形状灵活的butanamines中隔离和solvated的手术行为
Paul M Lemler1,2, Clayton L Craft1,3, Corina H Pollok1,4
1Department of Chemistry, Yale University, New Haven, Connecticut, USA.
Chirality
|August 7, 2023
概括
这项研究研究了灵活的阿利法胺的光学活性,揭示了溶剂极性显著影响了它们的手术反应. 了解这些效应对于预测不同环境中的分子行为至关重要.
科学领域:
- 物理化学 物理化学
- 频谱学是一种光谱学.
- 计算化学的计算化学
背景情况:
- 灵活的阿里法氨基体表现出复杂的形状格局.
- 了解它们的光学活动是预测分子行为的关键.
- 溶剂效应可以显著扰乱手术特征.
研究的目的:
- 探测 (2R) -3-甲基-2-butanamine (R-MBA) 和 (2R) -3,3) -二甲基-2-butanamine (R-DMBA) 的非共振光学活性.
- 检查构造性异构和溶剂扰动在光学旋转分散 (ORD) 上的作用.
- 将实验结果与量子化学计算的理论预测进行比较.
主要方法:
- 在六种不同的溶剂中测量了光学旋转分散 (ORD).
- 用密度函数理论 (DFT) 和合集群 (CC) 方法进行理论计算.
- 对于隐式溶解效应,使用了极化连续模型 (PCM).
- 使用独立合规替代器计算集成平均的ORD配置文件.
主要成果:
- 在320-590 nm区域内观察到R-MBA和R-DMBA的均负旋转功率.
- 随着溶剂介电常数的下降,手术视觉响应的大小增加.
- 蒸汽相特定的光学旋转最好通过高极性,低极性化溶剂 (如乙和甲醇) 来复制.
- 理论模型对孤立物种显示出合理的一致性,但对于溶液阶段的结果不太令人满意,特别是在极性溶剂中.
结论:
- 过渡状态能量和结构的溶剂介导的变化会影响溶液中的独立变压器替代品的有效性.
- 这项研究突出了在精确建模缩相中的柔性分子的手术特性的挑战.
- 需要进一步完善理论模型,以解释复杂的溶剂-溶解物相互作用.
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