(VI) 终端氧化物复合物的合成:分子几何由反向跨影响驱动
Boris Kosog1, Henry S La Pierre, Frank W Heinemann
1Inorganic Chemistry, Department of Chemistry and Pharmacy, Friedrich-Alexander-University of Erlangen-Nuremberg, Egerlandstrasse 1, 91058 Erlangen, Germany.
Journal of the American Chemical Society
|February 28, 2012
概括
合成和表征了新的 (VI) 氧复合物. 连接物修饰使终端 (VI) 氧复合体在没有转接物的情况下得到稳定,从而揭示了反转影响的洞察力.
科学领域:
- 无机化学 无机化学
- 有机金属化学 有机金属化学
- 化学 的化学
背景情况:
- (V) 氧复合物是 (VI) 氧物种的前体.
- 高价值的氧复合物通常表现出线性UO2 ((2+) 部分或需要转链体来稳定.
- 化 ((R) ArO) ((3) tacn ((3-) 连接体系统为稳定不寻常的氧化状态和几何形状提供了一个平台.
研究的目的:
- 合成和表征新的终端 (VI) 氧复合物.
- 研究连接体结构对 (VI) 氧复合物的几何和稳定性的影响.
- 在高价值化学中探索逆转影响的概念.
主要方法:
- 氧化 ((V) 前体的氧化过程.
- 使用 ((R) ArO) ((3) tacn(3-) 连接体系统合成(VI) 氧化合物.
- 用于结构确定的X射线晶体学.
- 密度函数理论 (DFT) 计算用于理论验证.
主要成果:
- 两个终端 ((VI) oxo复合物,2-t-Bu和2-Ad,已成功合成.
- 复杂的2-t-Bu与赤道平面上的氧联体呈现伪C(s) 对称性,容纳了一个转联体.
- 具有亚达曼基的复合物2-Ad稳定了没有转链体的C(3v) - 对称的终端(VI) 氧复合物.
- DFT计算量化了反向跨影响稳定在约6kcalmol (-1) 的数量.
结论:
- 联体设计对于控制氧复合物的协调环境和稳定性至关重要.
- 逆转变影响可以有效地稳定缺少转变配体的终端 (VI) 氧物种.
- 这项研究为高价值的基本反应性和协调化学提供了宝贵的见解.
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