关于在阿里亚化物和乙烯烯酸盐之间的 [3+2] 循环添加反应中中基中间体的问题
Ewa Dresler1, Przemysław Woliński2, Aneta Wróblewska3
1Łukasiewicz Research Network-Institute of Heavy Organic Synthesis "Blachownia", Energetyków 9, 47-225 Kędzierzyn-Koźle, Poland.
Molecules (Basel, Switzerland)
|December 23, 2023
概括
这项研究揭示了亚酸和乙烯烯酸盐之间的 [3+2] 循环添加反应遵循一个极性,单步机制. 之前提出的Zwitterionic中间体在主要反应途径中没有观察到.
科学领域:
- 有机化学 有机化学
- 计算化学的计算化学
- 反应机制 反应机制
背景情况:
- 循环添加反应是有机合成的基础.
- 了解反应机制对于预测反应性和设计新的合成路径至关重要.
- 之前的研究表明,在类似的反应中使用zwitterionic中间体.
研究的目的:
- 阐明化和乙烯烯酸盐之间的 [3+2] 循环添加反应的分子机制.
- 调查潜在的zwitterionic中间体的作用和形成.
- 应用分子电子密度理论 (MEDT) 进行详细的机械分析.
主要方法:
- 利用分子电子密度理论 (MEDT) 进行理论评估.
- 使用电子定位函数 (ELF) 分析.
- 研究的反应途径和中间结构.
主要成果:
- [3+2]循环添加通过极性,单步机制进行,不论化物替代剂.
- 试图定位先前假设的zwitterionic中间体是没有成功的.
- 具有"延伸"形状的兹维特里昂可以在平行反应路径上形成.
- 导致1,4-三的反应遵循一个两阶段,一个阶段的机制.
- 兹维特里昂的形成涉及从亚酸到乙 propiolate 的电子捐赠.
结论:
- 主要反应机制是一个极性,单阶段的过程,不涉及局部的zwitterionic中间体.
- 为了理解这些循环加法反应的复杂性,MEDT提供了一个强大的框架.
- 这项研究阐明了从酸和酸乙烯中形成1,4-三的机制性途径.
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