产生3-基-2,2-二酸的新型选择性环状反应:对机制的理论研究
Santiago Olivella1, Albert Solé, Oscar Jiménez
1Departament de Química Orgànica Biologica, Institut d'Investigacions Químiques i Ambientals de Barcelona, CSIC, Jordi Girona 18, 08034-Barcelona, Catalonia, Spain. sonqtc@cid.csic.es
Journal of the American Chemical Society
|February 24, 2005
概括
这项研究解释了一种新型的环形类反应,其中特定的子分裂了它们的CO-CF(3) 键. 密度功能理论计算显示,由于稳定,CO-CF(3) 键路径受到青.
科学领域:
- 有机化学 有机化学
- 计算化学的计算化学
- 反应机制 反应机制
背景情况:
- 环形类型的反应是重要的合成转化.
- 了解化反应的机制对于合成进步至关重要.
- 复杂分子中选择性键裂变需要详细的机械研究.
研究的目的:
- 为了合理化一种涉及化子的新型环状反应的实验结果.
- 阐明选择性CO-CF(3) 债券裂变的机制.
- 为了比较CO-CF(3) 与CO-CF(2) 键裂解路径的能量优势.
主要方法:
- 使用了密度函数理论 (DFT) 的计算,特别是B3LYP函数的计算.
- 模拟了气相反应路径和过渡状态.
- 使用自相一致的反应场 (SCRF) 形式主义与偏振连续模型 (PCM) 进行了溶剂效应的研究.
主要成果:
- 基促反应通过四面体中间体 (INT) 进行.
- 在能量方面,CO-CF(3) 债券的裂解比CO-CF(2) 债券的裂解更受青,具有较低的激活能量障碍.
- 在过渡状态下负电荷的原子稳定被确定为CO-CF(3) 债券选择性的关键因素.
结论:
- 该研究通过DFT计算成功合理化了前所未有的环形类型反应.
- 证实CO-CF(3) 债券的选择性裂变是占主导地位的途径.
- 计算发现为理解和潜在地控制合成化学中的这种反应提供了坚实的基础.
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