碳纳米管封闭在调节1,3-双极循环添加的区域选择性中的作用
Shuta Fukuura1, Takashi Yumura1
1Faculty of Materials Science and Engineering, Graduate School of Science and Technology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan.
The journal of physical chemistry. A
|August 12, 2023
概括
碳纳米管的封闭增强了1,3-双极循环添加反应中的区域选择性. 这项研究揭示了纳米管几何如何影响反应路径和产品形成,有利于1,4-triazoles.
科学领域:
- 计算化学计算化学
- 材料科学 材料科学 材料科学
- 有机合成 有机合成
背景情况:
- 1,3-双极循环添加反应对于合成像三醇这样的异环化合物至关重要.
- 碳纳米管 (CNT) 可以充当纳米反应器,可能影响反应结果.
- 了解限制对反应机制的影响对于设计新合成策略至关重要.
研究的目的:
- 在CNT中研究乙烯和化物之间1,3-双极循环添加的机制.
- 阐明CNT直径和几何在反应通路和区域选择性上的作用.
- 为了比较在封闭效应下1,4-和1,5-triazoles的形成.
主要方法:
- 基于密度函数理论 (DFT) 的计算用于模拟反应物种 (反应物复合物,过渡状态,产物).
- 对各种直径的CNT (10-14 Å) 内的反应进行了模拟.
- 分析的重点是几何特征,激活能量和反应中间体的轨道相互作用.
主要成果:
- CNT的限制显著增强了区域选择性,有利于1,4-triazoles的形成.
- 在1,4-方法中,平面反应物种经历的激活能量略有减少,独立于CNT直径.
- 在1,5方法中,在较薄的CNT中叠加基会增加由于排斥性轨道相互作用的激活能量.
结论:
- 纳米管封闭有效地控制了1,3-双极环添加物的区域选择性,促进了1,4-三醇的形成.
- 在CNT中的反应物种的直径依赖的几何学决定了激活能量的变化.
- DFT计算为循环加法反应的封闭效应提供了宝贵的见解,指导未来的合成应用.
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