乙烯:一种金属或碳基?
Dennis G H Hetterscheid1, Jasper Kaiser, Eduard Reijerse
1Radboud University Nijmegen, Institute for Molecules and Materials, Department of Metal-Organic Chemistry, Toernooiveld 1, NL-6525 ED Nijmegen (The Netherlands).
Journal of the American Chemical Society
|February 11, 2005
概括
复合物的单电子氧化产生稳定的Ir(II) -olefin物种,经历激进反应. 溶剂的选择和像TEMPO这样的激素捕捉剂会影响反应通路和产品的形成,产生化,桥式或化复合物.
科学领域:
- 有机金属化学 有机金属化学
- 协调化学 协调化学
- 激进化学 激进化学是什么
背景情况:
- 复合物与多牙氨基联体 (Me(n) tpa) 的复合物以其催化潜力而闻名.
- 一个电子氧化IrI) 复合体可以产生具有独特电子性质的反应性IrII) 物种.
研究的目的:
- 为了研究一电子氧化-乙烯复合体的反应性,[(Me(n) tpa) (II) 乙烯) ](2+).
- 探索溶剂供体能力和激素捕捉剂对反应通路的影响.
- 描述由此产生的物种及其电子结构.
主要方法:
- 电化学氧化[(Me(n) tpa) 铁 (I) 乙烯) ]+复合物.
- 反应中间体和产品的光谱表征 (UV-Vis,NMR) 的反应中间体和产品.
- 密度函数理论 (DFT) 计算以阐明电子结构和反应机制.
主要成果:
- 稳定的五坐标的Ir(II) -olefin物种,[Me(n) tpa) Ir(II) 乙烯](2+),被生成和特征.
- 证明了这些物种作为金属基的活性,其中的途径受到溶剂协调的影响.
- 观察到与NO和TEMPO的基结合,以及乙烯桥接和水解反应,导致各种复合物.
结论:
- 甲胺联体的电子和硬质性质以及溶剂供体能力调节了IrII) -olefin复合物的基质特性.
- 这些复合体作为多功能平台,用于在金属和乙烯中心探索激进化学.
- 控制的基因捕获允许选择性合成功能化的复合物.
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