合成一种稳定的化合物,在两个 (I) 中心之间具有五重键
Tailuan Nguyen1, Andrew D Sutton, Marcin Brynda
1Department of Chemistry, One Shields Avenue, University of California, Davis, CA 95616, USA.
Science (New York, N.Y.)
|September 24, 2005
概括
研究人员合成了一种稳定的化合物,表现出五倍的-结合,这是过渡金属化学的重大进步. 这一发现挑战了此前对这些元素多重键稳定性的限制.
科学领域:
- 无机化学 无机化学 有机化学
- 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:
- 过渡金属理论上可以形成多重键,但在室温下通常只有高达四重键才稳定.
- 以前的研究重点是实现过渡金属化合物中更高的债券订单.
研究的目的:
- 合成和表征一种具有高-键顺序的新型稳定化合物.
- 为了研究这种新化合物的结构和电子特性.
主要方法:
- 使用石墨减少一个前体{Cr(mu-Cl) Ar'}2.
- 由此产生的对空气和水分敏感的化合物的隔离和净化.
- 进行X射线衍射分析以确定Cr-Cr键的长度和分子几何.
- 温度独立的偏磁性测量.
- 计算研究以支持结合分析.
主要成果:
- 一种具有5倍-结合的稳定化合物Ar'CrCrAr'已成功合成,产量超过40%.
- X射线衍射揭示了一个短的Cr-Cr键长度为1.8351(4) 安格斯特罗姆和一个平面的横向核心.
- 实验和计算数据证实了两个 (I) 离子之间的五个电子对的共享.
结论:
- 这项研究表明,可以分离出一种稳定的化合物,其原子之间具有五重键.
- 这一发现扩大了过渡金属化学中多重键形成和稳定性的已知极限.
- 描述的化合物为探索高氧化状态,低坐标金属中心的化学提供了一个新的平台.
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