用DFT方法对4替代的pyrazolone衍生物进行结构性表征和-醇的分化
Serpil Eryilmaz1, Emine Bagdatli2
1Department of Physics, Faculty of Arts and Sciences, Amasya University, 05100, Amasya, Turkey.
Journal of molecular graphics & modelling
|July 5, 2024
概括
本研究合成和描述了两种pyrazolone衍生物,PYR-I和PYR-II,并使用光谱数据和DFT计算调查了它们的醇复合性. 结果显示,PYR-I倾向于基托形式,而PYR-II倾向于乙醇形式.
科学领域:
- 有机化学 有机化学
- 计算化学的计算化学
背景情况:
- 皮拉佐衍生物是药物化学中的重要支架.
- 了解乙醇复合性对于预测化学和生物性质至关重要.
研究的目的:
- 为了合成和描述两个新的pyrazolone衍生物,PYR-I和PYR-II.
- 通过实验和计算方法研究这些化合物的-醇复合.
- 为了确定首选的复合体状态,并分析合成化合物的反应性.
主要方法:
- 合成PYR-I和PYR-II. 这两种蛋白质.
- 使用FT-IR,NMR,UV-Vis和GC-MS进行表征.
- 密度函数理论 (DFT) 计算使用B3LYP/6-311++G(d,p).
- 优化分子几何形状和计算热力学参数 (ΔG, ΔH, ΔS, Keq, pKa).
- 自然键轨道 (NBO) 分析和边界分子轨道能量计算.
主要成果:
- 在实验和计算上发现,PYR-I在型中是稳定的.
- PYR-II在溶液中表现出型稳定性 (NMR),在固态中表现出型稳定性 (IR).
- DFT的计算证实,在各种条件下,基托-醇复合体平衡有利于PYR-I的基托形式和PYR-II的醇形式.
- NBO分析和反应性描述器提供了对最稳定的陶托默的化学行为的见解.
结论:
- 该研究成功合成和表征了两个pyrazolone衍生物.
- 阐明了PYR-I和PYR-II的醇-乙醇共聚性,揭示了对醇和乙醇形式的明显偏好.
- DFT计算提供了一种可靠的方法来预测分体偏好,并了解pyrazolone系统的反应性.
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