西拉环二烯和1,1-二化西拉环二烯的旋转光谱和环状结构
Nicole T Moon1, Amanda J Duerden1, Thomas M C McFadden2
1Department of Chemistry, Missouri University of Science and Technology, 400 W. 11th Street, Rolla, Missouri 65409, United States.
The journal of physical chemistry. A
|December 30, 2023
概括
使用微波光谱学研究了合成的西拉环-2-和1,1-二西拉环-2-. 实验结构和形状与量子化学预测相匹配,揭示了一个类似于环烯的"半椅子"结构.
科学领域:
- 有机化学 有机化学
- 分子光谱学 分子光谱学
- 计算化学计算化学
背景情况:
- 环素是含的循环有机化合物,在材料科学中具有潜在的应用.
- 了解它们的结构和特性对于开发新的基于的材料至关重要.
- 之前的研究已经探索了各种有机化合物,但对环素的详细结构分析是有限的.
研究的目的:
- 为了合成二氧化二烯和1,1-二氧化二烯.
- 用微波光谱学实验确定这些化合物的分子结构和构造.
- 将实验结果与量子化学计算进行比较.
主要方法:
- 合成西拉环合二烯和1,1-二氧化西拉环合二烯.
- 观察和分析跳脉冲,富里埃变换微波光谱.
- 使用B3LYP-D3BJ/Def2TZVP理论水平进行量子化学计算.
- 将光谱数据与一个半固的旋转哈密尔顿数相匹配.
主要成果:
- 两种分子的微波光谱都成功地被观察和分析.
- 量子化学计算预测了双极时刻组件,其中"a"组件是最大的,特别是对于二衍生物.
- 实验结构与计算结构密切匹配,两个分子采用类似于环烯的"半椅子"形状.
- 观察到包括29Si,30Si和13C在内的同位素在自然丰富.
结论:
- 该研究提供了详细的结构性特征的环二烯和1,1-difluorosilacyclohex-2-ene.
- 实验和计算结果非常一致,验证了使用的理论方法.
- 识别的"半椅子"形状为含循环系统的形状偏好提供了洞察力.
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