一个单金属 f 元素复合体的二: (C5Me5) 3U(eta1-N2)
William J Evans1, Stosh A Kozimor, Joseph W Ziller
1Department of Chemistry, University of California, Irvine, CA 92697-2025, USA. wevans@uci.edu
Journal of the American Chemical Society
|November 20, 2003
概括
固态阻碍的复合体与接体具有不同的反应性. (C5Me5) 3U与N2发生反应,而受阻较小的 (C5Me4H) 3U协调THF,突出了f元素化学中的固体效应.
科学领域:
- 有机金属化学 有机金属化学
- 化学 的化学
- 连接物反应性 连接物反应性
背景情况:
- 复合物与环丁联体是f元素化学中的关键.
- 了解连接体协调和反应性对于开发新的基材料至关重要.
- 金属中心周围的绝缘障碍显著影响反应性.
研究的目的:
- 为了比较固态拥挤 (C5Me5) 3U和较少拥挤 (C5Me4H) 3U与不同连接体的活性.
- 调查四基 (THF) 和二 (N2) 与这些复合物的协调行为.
- 阐明硬质体在决定反应路径中的作用.
主要方法:
- 复合物的合成和表征.
- 在不同的条件下,对四基 (THF) 和二 (N2) 的反应研究.
- 光谱分析 (例如,红外光谱) 和X射线晶体学以确定产品结构和粘合.
主要成果:
- 四氨酸 (THF) 坐标到较少拥挤的 (C5Me4H) 3U,形成 (C5Me4H) 3U (THF).
- THF的环开放发生在固态拥挤的 (C5Me5) 3U.
- 80 psi 的二 (N2) 与 (C5Me5) 3U 反应形成 (C5Me5) 3U(eta1-N2),其特点是 U-N 键长和 N2 拉伸频率.
- 只有未反应的 (C5Me4H) 3U 在80 psi的N2下被分离出来,表明没有反应或协调.
结论:
- 环二烯复合体中的固体阻碍决定了它们对常见和非传统联体的反应性.
- (C5Me5) 3U由于其拥挤的性质,与N2具有独特的反应性.
- (C5Me4H) 3U显示了与THF的优先协调,证明了固态可访问性对连接体选择的影响.
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