在6组末端二化合物上Al (C6F5) 3与B (C6F5) 3的协调:化学和结构差异
Léon Escomel1, Frederico F Martins2, Laure Vendier1
1LCC-CNRS, Université de Toulouse, CNRS UPS 205 Route de Narbonne, BP44099 F-31077 Toulouse Cedex 4 France antoine.simonneau@lcc-toulouse.fr.
Chemical science
|July 26, 2024
概括
三 (pentafluorophenyl) (AlCF) 与6组金属二化合物形成了强大的2:1附加物,与其类似物不同. 这些稳定的三核复合体显示出电催化减和可见光驱动固定的潜力.
科学领域:
- 有机金属化学 有机金属化学
- 协调化学 协调化学
- 超分子化学 超分子化学
背景情况:
- 6组金属复合物与素配体和二 (N2) 是固定研究的关键.
- 易斯超酸如三 (pentafluorophenyl) (BCF) 通过协调激活N2配体.
- 了解易斯酸相互作用对于设计新的催化剂至关重要.
研究的目的:
- 探索三三烯 (AlCF) 与6 bis组复合物的协调作用.
- 为了比较AlCF的反应性和结构特征与BCF的添加物.
- 研究由此产生的复合物的电子特性和潜在的催化应用.
主要方法:
- 合成和表征1:1和2:1的阿尔CF与[ML2(N2)2]复合体的添加物 (M = Cr,Mo,W;L =各种氨酸).
- 进行X射线晶体学以确定分离复合物的结构.
- 计算研究 (DFT) 用于分析电子结构,结合和反应机制.
- 紫外线光谱和TD-DFT计算用于研究电子转换.
主要成果:
- AlCF形成稳定的1:1 adducts,具有线性M-N-N-LA图案,类似于BCF,但由于固态排斥而具有结构差异.
- 与BCF不同的是,AlCF稳定地形成可分离的2:1附加物,这些附加物以更稳定的cis配置为异构.
- 这些2:1 adducts是第一个涉及p和d元素的三核异金属复合体,通过易斯酸相互作用形成.
- 计算显示,在AlCF协调时,HOMO-LUMO间隙减少,HOMO混合金属d和N2 π*轨道在cis-adducts中.
- 紫外线视频谱和TD-DFT揭示了涉及N2中心轨道的低MLCT波段,在易斯酸协调上出现红移.
结论:
- AlCF是一种强大的易斯酸,能够与二联体形成稳定,可分离的多核复合体.
- 由AlCF协调引发的电子修饰表明了对N2和电子转移的增强电友性攻击的潜力.
- 这些发现为开发易斯酸辅助的电催化和可见光驱动的固催化剂开辟了道路.
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