1,3,5-三二二三基是一种环二基的类似物吗?
Harvey A Lardin1, John J Nash, Paul G Wenthold
1Department of Chemistry, Purdue University, West Lafayette, Indiana 47907-1393, USA.
Journal of the American Chemical Society
|October 17, 2002
概括
这项研究使用负离子热化学循环确定了1,3,5-三二二三基的形成热量. 这些发现提供了对的洞察力.
科学领域:
- 物理化学 物理化学
- 热化学 热化学 热化学
- 量子化学 是一个量子化学.
背景情况:
- 1,3,5-三二二三基是高度反应的中间体.
- 了解其热化学特性对于反应机制研究至关重要.
研究的目的:
- 通过实验确定1,3,5-三二二三基的形成气相热量.
- 在m-的5位上计算键解离能 (BDE).
- 将实验结果与理论计算进行比较,并探索电子结构的相似性.
主要方法:
- 使用负离子热化学循环.
- 测量了3,5-二二酸的气相酸度.
- 为3,5-二二酸盐的脱碳化和3,5-二二二二的化物损失而确定的度.
- 测量了5-chloro-m-benzyne的电子亲和力和化物损失值.
主要成果:
- 对于5-chloro-m-benzyne的形成热量被确定为116.2 ± 3.7 kcal/mol.
- 对于1,3,5-三二二三基的形成热量测量为179.1±4.6 kcal/mol.
- 在m-的5位置的BDE计算为109.2±5.6 kcal/mol,低于中的第一个BDE.
结论:
- 1,3,5-三二二基可以被视为一种与m-部分弱相互作用的基.
- 实验BDE值与多引用配置交互计算非常一致.
- 三基基的电子结构与环烯基系统有相似之处.
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