终端桥梁二复合体
David H Woen1, Guo P Chen1, Joseph W Ziller1
1Department of Chemistry, University of California, Irvine , Irvine, California 92697-2025, United States.
Journal of the American Chemical Society
|September 29, 2017
概括
研究人员合成了第一个稀土金属端复合物,具有独特的Sc-N2-Sc桥梁. 这一发现为稀土化学中的结和反应性提供了新的见解.
科学领域:
- 无机化学
- 有机金属化学
- 稀土化学
背景情况:
- 已经描述了40多个具有侧向桥梁的稀土金属二化合物.
- 这些复合物的结构多样性和反应性尚未完全理解.
研究的目的:
- 合成和表征一种稀土金属复合物,
- 调查这个新型复合体的结构和电子特性.
- 探索终端二复合物的反应性和光化学.
主要方法:
- 在35°C下降低Sc (NR2) 3.
- 用X射线结晶学进行结构测定.
- 通过拉曼光谱分析N-N键.
- 埃文斯方法和DFT计算用于研究磁性和电子结构.
主要成果:
- 在稀土金属复合体中,第一个终端二桥,{K(crypt) }2{[(R2N) 3Sc]2[μ-η1:η1-N2]},已成功合成和表征.
- N-N 键距离 (1.221(3) Å) 和拉曼拉伸 (1644 cm-1) 证实了 (NN) 2 的特征.
- DFT计算和磁性测量表明Sc2N2核心的三重基态.
- 在紫外线下的光解导致单体Sc2+复合物的形成,表明光诱导的反应性.
结论:
- 末端二复合物的合成与先前已知的侧面复合物具有显著的结构差异.
- 金属结合剂在二结合的可逆性中起着至关重要的作用,这是由密室和皇冠以太系统之间的比较证明的.
- 这项研究为探索稀土金属对二激活和转化的基本化学过程开辟了新的途径.
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