通过monoanionic dialkyldiarylguanidinato连接物稳定 (IV) 的稳定
1Department of Chemistry, The University of Iowa, Iowa City, Iowa 52242, USA. jan-uwe-rohde@uiowa.edu
Journal of the American Chemical Society
|July 2, 2009
概括
研究人员合成了富含电子的,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,) 的复合物. 这些复合物经历可逆氧化,形成稳定的 (IV) 化合物,展示了与联体的新可访问的氧化状态.
科学领域:
- 有机金属化学 有机金属化学
- 无机化学 无机化学
- 协调化学 协调化学
背景情况:
- 的三 (((guanidinato) 复合物是富含电子的,可以合成.
- 了解金属复合物的电化学特性和可访问的氧化状态在协调化学中至关重要.
研究的目的:
- 合成和表征新的富含电子的三 () 复合物和 (III) 复合物.
- 研究这些 (III) 复合物的电化学氧化行为.
- 为了探索 ((IV) 氧化状态在捐赠体连接体环境中的可访问性.
主要方法:
- 从[Ir{ArNC(NR(2)) NAr}(C(8) H(14)) ((2)) ]前体中合成 (III) 三 () () 化合物.
- 电化学氧化研究,以确定电子转移步骤和潜力.
- 使用[FeCp(2)]PF(6) 的化学氧化,以分离(IV) 化合物.
- 使用分析和光谱方法进行表征,包括单晶X射线衍射.
主要成果:
- 成功合成了富含电子的Ir(III) 的tris(guanidinato) 复合体.
- 这些复合体表现出两个单电子转移氧化阶段,第一个是可逆的,发生在异常低的Ir(III) 电位时.
- 通过化学氧化分离和表征了对磁性Ir(IV) 化合物,证实了这种更高氧化状态的可获得性.
结论:
- 这项研究证明了富含电子的Ir(III) guanidinato复合物的成功合成和表征.
- 在捐赠体连接体环境中,可以获得Ir (IV),从而扩展了已知的的协调化学.
- 可逆和低电位的第一氧化阶段突出了这些复合物的独特电子特性.
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