通过使用简单的胺和氧化物联体,通过TmII,DyII和NdII减少二
William J Evans1, Gaël Zucchi, Joseph W Ziller
1Department of Chemistry, University of California, Irvine, CA 92697-2025, USA. wevans@uci.edu
Journal of the American Chemical Society
|January 8, 2003
概括
新的研究表明,双价兰坦化物如 (Tm), (Dy) 和 (Nd) 可以将气 (N2) 减少到新的平面结构. 这一突破避免了复杂的连接物,利用简单的胺和氧化连接物来减少二.
科学领域:
- 无机化学 无机化学
- 有机金属化学 有机金属化学
- 固定的方法是固定.
背景情况:
- 气 (N2) 是丰富的,但惰性,这对化学减少构成了重大挑战.
- 传统的减少N2的方法通常需要恶劣的条件或复杂的连接体系统.
- 双元胺复合体为探索N2激活和减少提供了一个新的途径.
研究的目的:
- 研究双价兰化物复合物在降低二 (N2) 的潜力.
- 探索使用简单的,常见的连接体来促进二氧化碳的减少.
- 描述由此产生的缩产品的结构和结合.
主要方法:
- 合成双价兰化物复合物 (LnI2,其中Ln = Tm,Dy,Nd).
- LnI2与二三甲基胺 (NaN (SiMe3) 2) 或二氧化 (KOC6H3tBu2-2,6) 的反应.
- 使用X射线晶体学对产生的二复合物的结构性表征.
主要成果:
- 与胺配体的二元Tm和Dy复合物减少了N2以形成平面Ln2N2单元,NN键长为1.264{\displaystyle 1.264} (7) 和1.305{\displaystyle 1.305} (6) Å,表明 (N2) 2−部分.
- 一个双价Nd复合体与氧化物连接体形成了一个类似的平面Nd2N2结构,NN键的长度较短,为1.242{\displaystyle 1.242}{\displaystyle 1.242}{\displaystyle 1.242}{\displaystyle 1.242}{\displaystyle 1.242}{\displaystyle 1.242}{\displaystyle 1.242}{\displaystyle 1.242}{\displaystyle 1.242}{\displaystyle 1.7}).
- 这种减少在没有循环丁烯酸或多丁酸连接剂的情况下实现.
结论:
- 双价兰化物 (Tm,Dy,Nd) 是二 (N2) 的有效减少剂.
- 简单的单一牙胺和氧化物连接体足以通过这些双价兰坦化物减少N2.
- 这项研究展示了一种新的,可能更简单的固定途径,使用可访问的化物复合物.
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