在zw-type [3 + 2] 循环添加反应中,氧化与有多大不同? 一个分子电子密度理论研究研究研究
Luis R Domingo1, Patricia Pérez2
1Avd. Tirso de Molina 20, 46015 Valencia, Spain.
The Journal of organic chemistry
|March 7, 2025
概括
由于它们的中度电友和核友性质,尼氧化物 (BNO) 在zw型 [3 + 2] 循环添加反应中具有较低的反应性. 它们与核友乙烯反应更好,表现出明显的区域选择性.
科学领域:
- 有机化学 有机化学
- 理论化学 理论化学
- 计算化学计算化学
背景情况:
- onitrile氧化物 (BNO) 是有机化学中的多功能合成物.
- 了解BNO在循环添加反应中的反应性对于合成应用至关重要.
- zw型 [3 + 2] 循环添加 (32CA) 是形成五个成员异环的关键反应.
研究的目的:
- 在zw型32CA反应中研究BNOs的低反应性.
- 分析BNOs和乙烯的电子结构和反应率指数.
- 阐明这些循环加法反应中支配区域选择性和激活能量的因素.
主要方法:
- 分子电子密度理论 (MEDT)
- 基于密度函数理论 (DFT) 的反应性指数分析分析.
- 电子定位函数 (ELF) 拓分析
- 激活能量分析 激活能量分析
- 相对相互作用的原子能分析.
主要成果:
- 在BNOs上的副替代不会显著改变CNO框架中的电子密度分布.
- 非替代的BNO充当中等电友和核友,解释了其在极性反应中的有限反应性.
- 对于具有强核性乙烯,BNOs的反应更有效,而不是对具有强电性乙烯的反应.
- 与核友乙烯的32CA反应是正区域选择性的,而与电友乙烯的反应表现出较差的元区域选择性.
- 电友BNO框架与超核友乙烯的更强稳定性与更高的反应性相关.
结论:
- 在zw型32CA反应中,BNOs的电子特性决定了它们的反应性.
- 由于有利的框架稳定,强核性乙烯增强了反应性.
- 区域选择性取决于乙烯合作伙伴的电子性质.
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