复合物中的联体诱导的分子内氧化多样性与乙烯-1,2-二胺胺
Alexander G Morozov1, Vladimir A Dodonov1, Elena A Rychagova1
1G. A. Razuvaev Institute of Organometallic Chemistry of Russian Academy of Sciences (IOMC RAS), Tropinina 49, Nizhny Novgorod 603950, Russian Federation.
Inorganic chemistry
|February 24, 2024
概括
这项研究详细介绍了新型的复合物与不同的氧和联体,揭示了联体结构如何影响它们的几何,稳定性和电子性质. 这些发现突出了更多的基团的稳定性,影响了THF等溶剂的反应性.
科学领域:
- 有机金属化学 有机金属化学
- 协调化学 协调化学
- 计算化学计算化学
背景情况:
- 复合物与重的二胺配体对催化和材料科学有兴趣.
- 了解连接体结构和金属中心特性之间的关系对于设计新的功能分子至关重要.
- 辅助连接体对的电子和硬质环境的影响尚未完全阐明.
研究的目的:
- 为了合成和描述一系列含有1,2-bis[(2,6-diisopropylphenyl) imino]acenaphthene (dpp-Bian) 连接体的化物和氧化复合物.
- 研究不同类型的氧和联体替代对这些复合物的协调几何学,电子结构和反应性的影响.
- 通过密度函数理论 (DFT) 计算获得的理论见解与实验发现的相关性.
主要方法:
- 新型复合物的合成具有一般公式 (dpp-Bian) Ti(OPr) Cl3-, (dpp-Bian) Ti(OPr) 2,和 (dpp-Bian) Ti(OPr) Cl3.
- 使用单晶X射线衍射,光谱研究 (包括电子磁共振) 和密度函数理论 (DFT) 计算进行了表征.
- 分析电荷和自旋密度分布,分子轨道能量,电子过渡能量和反应热力学.
主要成果:
- 化合物 2-4 呈现出正方形-金字塔形状的几何形状,其中有单离子dpp-Bian,而3-Cl (中性二胺) 和5 (二离子恩胺) 分别显示出八面体和四面体的协调.
- 偏磁复合体 2-4 显示了自旋密度转移到dpp-Bian联体,随着基群数的增加而增加.
- 系列2 < 3 < 4中的增强的Ti-N键极性导致对O-捐赠分子的稳定性增加,复合物4在THF中稳定,而2和3经历了可逆溶解.
结论:
- 复合物的协调几何学和电子性质受到辅助醇基和联体的性质和数量的显著影响.
- 增加的醇基替代增强了复合物的稳定性,通过加强Ti-N键和减少对溶剂分子的反应性来提高复合物的稳定性.
- DFT计算为这些有机金属化合物的电子结构,结合和反应性提供了宝贵的见解,补充了实验观测.
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