从Mo-Mo四倍债券到五倍债券的旅程
Yi-Chou Tsai1, Hong-Zhang Chen, Chie-Chieh Chang
1Department of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan, ROC. yictsai@mx.nthu.edu.tw
Journal of the American Chemical Society
|August 19, 2009
概括
研究人员合成了具有四倍和五倍键的新型二molybdenum复合物. 这些复合体表现出迄今为止观察到的最短的金属对金属债券,超出了第一行元素,由DFT计算证实.
科学领域:
- 无机化学 无机化学
- 材料科学 材料科学 材料科学
- 计算化学计算化学
背景情况:
- 已知二molybdenum复合物表现出多重金属对金属的键.
- 轮结构在二molybdenum化学中很常见.
- 探索更高阶的金属-金属键对于理解化学结合至关重要.
研究的目的:
- 合成和表征具有四重和五重键的新型二聚烯复合物.
- 调查这些新型复合体的结构和电子特性.
- 为了探索超出第一行元素的最短金属-金属键的形成.
主要方法:
- 通过K(4) Mo(2) Cl(8) 与Li[RC(NDipp) ((2) ]配体的反应合成二聚复合物.
- 使用X射线晶体学进行结构性表征.
- 使用密度函数理论 (DFT) 计算的电子结构分析.
主要成果:
- 合成了两种轮类型的四重结合的二聚复合物Mo(2)(mu-Cl)[Cl(2)Li(OEt(2))][mu-eta(2)-RC(N-2,6-i-Pr(2)C(6)H(3))(2)](2),这些复合物被用于合成.
- 这些复合物的减少产生了Mo-Mo五重键复合物,Mo(2) [mu-eta(2) -RC(N-2,6-i-Pr(2) C(6) H(3)) ((2)) ](2),其Mo-Mo键长短明显.
- 由此产生的Mo-Mo键长代表了在第一行元素之外观察到的最短的金属-金属键.
结论:
- 具有四倍和五倍键的二聚烯复合物的成功合成扩大了无机化学中多重键的范围.
- 观察到的最短的金属对金属的结合提供了关于重过渡金属结合性质的见解.
- DFT计算证实了五重键的存在以及合成复合物的结构特征.
相关概念视频
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