使用-迈克尔反应制造烯酸酸zwitterions
Matthias R Steiner1,2, Max Schmallegger3, Larissa Donner1,2
1Institute for Chemistry and Technology of Materials, Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria.
Beilstein journal of organic chemistry
|January 17, 2024
概括
研究人员通过与迈克尔受体的反应合成了九种新型的酸 fenolate zwitterions. 这些化合物表现出独特的电子特性,它们的形成动力学揭示了决定速率的质子转移步骤.
科学领域:
- 有机化学化学 有机化学
- 超分子化学 超分子化学
- 有机合成 有机合成
背景情况:
- 盐和酸盐是多用途的化学实体.
- 迈克尔受体在有机合成中对于碳-碳键形成至关重要.
- 了解zwiwterion形成机制是设计新分子的关键.
研究的目的:
- 合成和表征新的烯酸酸zwitterions. 为了合成和表征新的烯酸.
- 为了研究这些zwitterions的结构和电子特性.
- 阐明它们形成的动力学和机制.
主要方法:
- 2,4-di-tert-butyl-6-(diphenylphosphino) phenol与各种迈克尔受体的反应.
- 合成和九个zwitterions的完整表征.
- 单晶X射线晶体学用于固态结构的确定.
- 核磁共振 (NMR) 光谱学.核磁共振 (NMR) 光谱学.
- 紫外线光谱学.紫外线光谱学.
- 用不同溶剂 (甲和甲醇) 进行动力学研究.
主要成果:
- 已经成功合成和特征化了9个烯酸酸 (phosphonium phenolate zwitterions).
- 固态结构显示出显著的圆形共振贡献.
- 兹维特里昂在360nm左右显示紫外线的吸收,具有负的solvatochromism.
- 动力分析确定了质子转移作为速度决定的步骤.
- 反应性受到迈克尔接受器结构和溶剂极性的影响.
结论:
- 这项研究成功地合成和表征了新型的烯酸 (phosphonium phenolate zwitterions).
- 力共振在这些分子的电子结构中起着至关重要的作用.
- 形成机制取决于迈克尔受体进行预组织的能力和溶剂的性质.
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