内分子供体稳定四协调 ((iv) 滴和它们的易斯酸性质
Balakrishna Peddi1, Souvik Khan1, Rajesh G Gonnade2
1Department of Chemistry, Indian Institute of Science Education and Research, Pune Dr. Homi Bhabha Road, Pashan Pune-411008 Maharashtra India moumitam@iiserpune.ac.in.
Chemical science
|December 11, 2023
概括
这项研究引入了由素连接体稳定的新型四协调 ((IV) 二化合物. 这些化合物在激活Si-H键和催化水化反应方面表现出独特的反应性,其中一种化合物表现出掩盖的丧的易斯对行为.
科学领域:
- 有机金属化学 有机金属化学
- 主群 化学 化学
- 催化剂是一种催化剂.
背景情况:
- 由于其独特的电子和结构性质,四协调 (IV) 化合物引起了人们的兴趣.
- 素配体对于稳定反应性金属中心和影响催化活性至关重要.
- 丧的易斯对 (FLP) 是小分子激活和催化的一个强大概念.
研究的目的:
- 合成和表征新的分子内稳定四协调 ((IV) 二化合物.
- 为了研究这些复合物的电子结构,几何和反应性.
- 探索它们在水化反应中的催化剂的潜力,并了解它们的催化机制.
主要方法:
- 中性,单离子和二离子 (IV) 前体的逐步合成.
- 使用光谱技术和X射线晶体学进行表征.
- 密度函数理论 (DFT) 研究以阐明电子结构和电荷分布.
- 在芳香性化物水化过程中进行催化试验.
主要成果:
- 成功合成了两个四协调 (IV) 二化合物,LiPr2Ge][CF3SO3和LPh2Ge][CF3SO3,具有受约束的螺旋几何.
- DFT的计算显示了P-Ge-P框架上的电荷移位,离子/易斯基结合改变了几何.
- 化合物3iPr和3Ph激活Si-H键,而化物迁移到发生的速度不同.
- 催化研究表明,3iPr激活Et3Si-H,而3Ph显示在水化中掩盖的丧的易斯对 (FLP) 反应性.
结论:
- 已经合成了分子内素稳定四协调 (IV) 二化合物的第一个例子.
- 这些化合物具有独特的电子特性和反应性,包括Si-H键激活.
- 在水化中的催化性能突出了不同的机制,其中一个化合物模仿FLP行为.
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