打开外的合成,双金属的Mn/Fe三核集群
Tamara M Powers1, Nina X Gu, Alison R Fout
1Department of Chemistry and Chemical Biology, Harvard University , 12 Oxford Street, Cambridge, Massachusetts 02138, United States.
Journal of the American Chemical Society
|August 30, 2013
概括
研究人员使用六酸连接体平台合成了新的混合金属集群. 这项研究证明了联结体的存在.
科学领域:
- 协调化学 协调化学
- 有机金属化学 有机金属化学
- 材料科学 材料科学 材料科学
背景情况:
- 六酸联体为金属离子提供了多功能协调环境.
- 过渡金属集群在催化和材料科学中至关重要.
- 开发混合金属集群的合成路线仍然是一个挑战.
研究的目的:
- 探索使用六联体平台对同质三核和双金属三核集群的合成.
- 为了研究连接体支持混合金属集群形成的能力.
- 了解影响混合金属集群中金属替代的因素.
主要方法:
- 用Fe或Mn前体对LH6的六酸联体 (tbs) 进行脱和金属化.
- 同核三核和双核复合体的分离和表征.
- 使用双核物种作为合成子的双金属三核集群的合成.
- 光谱和晶体分析包括NMR,莫斯巴尔光谱,X射线光和异常散射.
主要成果:
- 分离了同质三核复合体 ((tbs) L) Fe3 ((THF) 和 ((tbs) L) Mn3 ((THF).
- 双核复合物 ((tbs) LH2) M2 (M = Fe或Mn) 在没有协调溶剂的情况下形成.
- 六酸连体成功支持二金属三核的形成,例如, ((tbs) L) Fe2Mn ((THF).
- 在混合金属集群形成中观察到热力学偏好更重金属替代.
结论:
- 六酸合体合体平台 (tbs) LH6 能够对同质三核和混合金属集的受控合成.
- 这项工作为组装公正的混合金属集群建立了新的途径.
- 这些发现提供了关于多核复合体中金属分布的热力学控制的见解.
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