探测性地过渡金属结合的极限:一个实验和计算研究
Matthew P Blake1, Nikolas Kaltsoyannis2, Philip Mountford1
1Chemistry Research Laboratory, Department of Chemistry, University of Oxford , Mansfield Road, Oxford OX1 3TA, United Kingdom.
Journal of the American Chemical Society
|September 5, 2015
概括
合成了新的土金属 (Ae) 和甲基 (Ln) 化合物. 这些金属与之间的结合相互作用有很大差异,影响化合物的结构和稳定性.
科学领域:
- 有机金属化学
- 协调化学
- 材料科学
背景情况:
- 土金属 (Ae) 和化物 (Ln) 在各种化学应用中都很重要.
- 了解有机金属复合物的金属结合对于设计新材料至关重要.
- 之前的研究已经探讨了金属配体相互作用,但Ae-TM和Ln-TM结合需要进一步研究.
研究的目的:
- 用过渡金属碳片合成和表征新型Ae和Ln复合物.
- 研究土/化金属与过渡金属 (TM) 之间的结合性.
- 探讨金属电荷与尺寸的比率以及对金属结合的连接效应的影响.
主要方法:
- 使用Mg,Ca,Sr,Ba,Yb,Eu和Sm合金来减少过渡金属碳化合物.
- 新型Ae和Ln有机金属化合物的合成和分离.
- 使用扩散NMR光谱等技术进行表征.
- 计算分析包括密度函数理论 (DFT) 和齐格勒·劳克能量分解.
主要成果:
- 合成了类型[M{Co(CO) 3(PCy3) }2(THF) n]2的新二次化合物,其中M = Ae或Ln.
- 这种M-Co结合模式因金属的电荷与大小的比率而异,从直接的M-Co结合到异碳酸结合 (η(1) 和侧面协调 (η(2)).
- DFT的计算显示了Ae-Co相互作用能量的下降,并突出显示了直接结合和CO连体协调之间的竞争.
结论:
- 土和化金属的电荷与大小的比率显著决定了它们与过渡金属碳酸的结合相互作用.
- 连接物选择,特别是重的PCy3连接物,提高了溶解度,并影响了金属与金属的相互作用能量.
- 计算方法为这些金属结合的性质和强度提供了宝贵的见解,指导了未来的合成努力.
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