异常短的H⋅⋅⋅H接触在内分子循环的螺旋合的人类中
Hiroki Fukuda1, Eiji Tsurumaki1, Kan Wakamatsu2
1Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo, 152-8551, Japan.
Chemistry (Weinheim an der Bergstrasse, Germany)
|May 16, 2024
概括
亚马莫托对二甲的合产生了硬质阻碍,扭曲的分子. 这些螺旋结构表现出不寻常的-接触,影响了它们的光谱特性和反转障碍.
科学领域:
- 有机化学 有机化学
- 超分子化学 超分子化学
- 立体化学是一种立体化学.
背景情况:
- 螺旋化多环芳 (PAHs) 由于其独特的结构和电子特性而引起人们的兴趣.
- 分子架构中的固体拥堵可以导致新的构造和反应性.
研究的目的:
- 通过分子内合合成和表征绝缘拥挤的,循环的炭烯.
- 研究这些独特的分子系统的结构,光谱和动态特性.
主要方法:
- 亚马莫托合用于分子内循环.
- 用希尔什菲尔德原子精制的X射线晶体学.
- 密度函数理论 (DFT) 的计算.
- 核磁共振 (NMR) 光谱 (1小时NMR,动态NMR).
- 红外 (IR) 光谱学.红外 (IR) 光谱学.
- 非共价相互作用 (NCI) 图. 非共价相互作用 (NCI) 图.
主要成果:
- 成功合成了循环,无菌地拥挤的,具有扭曲的,非平面结构的炭烯.
- X射线分析显示,在拥挤的核心内,H-H距离异常短 (1.648-1.692 Å).
- 光谱数据 (1H NMR,IR) 支持显著的固态阻碍和电子效应.
- DFT计算和NCI图表证实了非平面形状和硬质环境.
- 一个高的螺旋倒置障碍 (84 kJ/mol) 确定为一个 mesityl-substituted衍生品.
结论:
- 该研究表明,通过山本合,形成高度拥挤的螺旋结构.
- 短暂的分子内-接触显著影响分子构造和光谱特征.
- 合成的化合物作为模型来研究复杂芳香系统中的固态效应和分子动力学.
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