环衍生物中的开与封闭结合相互作用:EDA-NOCV分析EDA-NOCV分析
Sonam Suthar1, Kartik Chandra Mondal1
1Department of Chemistry, Indian Institute of Technology Madras, Chennai, India.
Journal of computational chemistry
|August 2, 2023
概括
大多数环环中的化学结合涉及原始共价键,不同于典型的电子共享键. 这一发现为这些常见的有机结构提供了更一般的结合模型.
科学领域:
- 有机化学 有机化学
- 计算化学的计算化学
- 量子化学 是一个量子化学.
背景情况:
- 环环在有机和生物有机化合物中普遍存在,具有独特的压力C3环.
- 一个多世纪以来,环烯的化学结合和反应性一直在争论中,Bent-Bond和Walsh等模型.
- 了解环烯结合对于合理化其稳定性,反应性和物理性质至关重要.
研究的目的:
- 用先进的计算方法研究环烯C-C键的结合性质.
- 通过分析各种功能化化合物,开发一个更一般的环环结合模型.
- 阐明功能组对环烯系统中的化学结合的影响.
主要方法:
- 使用能量分解分析与化学价值自然轨道 (EDA-NOCV) 结合,对49种含有环环的不同有机化合物进行分析.
- 分析了碎片轨道和键形成,以描述环旋环内的C-C键的性质.
- 利用分子中的原子量子理论 (QTAIM) 分析来补充EDA-NOCV的发现.
主要成果:
- EDA-NOCV分析显示,大多数环烯C-C键 (37/49化合物) 喜欢形成两个dative共价键,而不是两个电子共享键.
- 一小部分化合物 (7/49) 呈现电子共享键,而一些 (5/49) 显示了两种键类型之间的灵活性.
- QTAIM的分析支持了这些发现,显示了与典型的碳化合物单一键相比,环烯的C-C键具有不同的参数.
结论:
- 环环中占主导地位的结合涉及原始共价相互作用,挑战了传统的结合描述.
- 该研究提供了一个更普遍的环烯的结合模型,适用于各种功能化的系统.
- 环环的粘合特性与金属烯系统有相似之处.
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