(III) (NHC) ⋅AlMes+:在FLP化学中的合成,表征和应用
Luis Werner1, Julika Hagn1, Janis Walpuski1
1Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.
Angewandte Chemie (International ed. in English)
|October 25, 2023
概括
通过N-异环碳 (NHCs) 稳定新的酸被合成. 这些易斯酸表现出增强的酸度,使得与素配对时能够与小分子发生反应,形成挫败的易斯对 (FLP).
科学领域:
- 有机金属化学 有机金属化学
- 易斯酸化学 易斯酸化学
- N-异环碳化合物的化学成分
背景情况:
- 在有机金属化学中,N-异环碳 (NHCs) 是多功能联体.
- 化合物是众所周知的易斯酸,具有多种应用.
- 开发新的易斯酸性物种对于催化和合成至关重要.
研究的目的:
- 为了合成和表征由NHC连接体稳定的新型三坐标离子.
- 为了研究这些新复合物的易斯酸度.
- 探索这些复合物的反应性,特别是在挫败的易斯对 (FLP) 的形成中.
主要方法:
- 从阿兰中提取化物,使用多或二甲基乙醇中的三甲基离子.
- 三和四坐标酸的隔离和表征.
- 易斯酸度的理论和实验评估.
- 与氨酸发生反应,形成混合的NHC/氨酸和FLP.
主要成果:
- 合成三坐标酸[(NHC) ⋅AlMes2]+和四坐标乙酸[(NHC) ⋅AlMes2(OEt2)]+的合成.
- 实验和理论数据表明,[(IMeMe) ⋅AlMes2]+的易斯酸度很高,与Al(C6F5)3.3相比.
- 形成一个混合的NHC/素稳定离子[(IMeMe) ⋅AlMes2(PMe3) ]+.
- 从[(IMeMe) ⋅AlMes2]+和PCy3生成一个挫败的易斯对 (FLP),该对与CO2,乙烯和2-丁烯发生反应.
结论:
- 已经成功合成了具有显著易斯酸度的新型NHC稳定三坐标酸.
- 这些易斯酸性物种可以与素形成FLP,对小分子表现出反应性.
- 这些发现为开发基于-NHC化学的新催化剂和试剂开辟了道路.
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