过渡金属稳定的酸:二协调到pi基础金属碎片的的质子化
Joseph M Keane1, Mahendra D Chordia, Christopher J Mocella
1Department of Chemistry, University of Virginia, Charlottesville, Virginia 22901, USA.
Journal of the American Chemical Society
|May 27, 2004
概括
新的金属复合物中含有化 ((pyrazolyl) 酸盐连接物,表现出增强的基本性,在质子化后形成稳定的酸. 这些发现推进了有机金属化学和催化.
科学领域:
- 有机金属化学 有机金属化学
- 协调化学 协调化学
- 催化剂是一种催化剂.
背景情况:
- 基是具有多种应用的基本有机分子.
- 金属-烯复合物在催化和材料科学中至关重要.
- 了解金属相互作用的电子特性是设计新催化剂的关键.
研究的目的:
- 为了合成和表征新的pi-基础金属碎片与dihapto-coordinated arenes.
- 与现有系统相比,研究这些新领域综合体的基本性.
- 探索质子化离子复合物的形成和稳定性.
主要方法:
- 金属复合物的合成一般形式是[TpM (p) 酸 (p) 酸 (L) ],其中Tp = 水酸 (p) 酸,M = Re,Mo,W,pi酸 = CO或NO (p) 酸+),L = 伊米达,皮里丁或三甲基.
- 使用中度酸形成离子的质子化研究.
- 进行X射线晶体学以确定关键复合物的结构,包括[TpRe(CO) ((MeIm) ((5,6-eta(2)-2H-anisolium) ](OTf).
主要成果:
- 合成了一系列的金属复合物与二合协调.
- 证明这些复合物比胺基 (pentaammineosmium) 的类型更为基本.
- 通过质子化获得稳定的eta(2) 和eta(3) 离子复合体.
- 晶体结构证实了eta(2) 协调,并暗示了一个弱的金属-体相互作用.
结论:
- 合成的化 (pyrazolyl) 酸盐金属复合物代表了一种新型的高度基本的协调化合物.
- 增强的基本性促进了稳定的离子的形成,为新的反应性开辟了道路.
- 这些发现有助于对金属-烯结合的基本理解,并对催化剂设计产生影响.
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