二氧化碳激活,用压力绝缘的中高价值复合体进行激活
Suzanne C Bart1, Christian Anthon, Frank W Heinemann
1University of Erlangen-Nürnberg, Department of Chemistry and Pharmacy, Inorganic Chemistry, Egerlandstrasse 1, 91058 Erlangen, Germany.
Journal of the American Chemical Society
|August 22, 2008
概括
压缩的复合物激活二氧化碳,形成新的 (V) imido,oxo和碳酸盐物种. 对连接体支架的立体效应决定了反应路径和产品结构,揭示了不寻常的电子性质.
科学领域:
- 有机金属化学 有机金属化学
- 化学 的化学
- 二氧化碳激活方式
背景情况:
- 固态阻碍复合体是理解反应性的关键.
- 三环旋无联体提供可调节的固态环境.
- 二氧化碳的激活仍然是化学中的一个重大挑战.
研究的目的:
- 为了研究二氧化碳的激活和转化通过压缩复合体.
- 为了合成和描述高价值的imido,oxo和carbamate物种.
- 阐明体体质量对反应机制和产品结构的影响.
主要方法:
- 复合物的合成和光谱表征.
- 用X射线晶体学来确定分子结构.
- 电子吸收,EPR光谱,SQUID磁化和DFT研究用于电子结构分析.
主要成果:
- 合成 (V) imido复合物,其中有曲的imido碎片和长的U-N键.
- 通过二氧化碳反应的异酸挤出形成 (V) 终端氧物种.
- 观测(V) 碳酸盐中间体和二烯酸衍生物.
- (IV) 碳酸盐复合物的表征来自于CO2插入到U-N胺键中.
- 通过结合体支架在碳酸盐协调模式 (单牙与双牙) 上展示了固态控制.
结论:
- 压缩的复合物有效地激活和转化二氧化碳.
- 连接体的固态环境决定了反应路径和由此产生的碳酸盐物种的协调.
- 高价值的氧复合物表现出不寻常的电子特性,表明了新的结合相互作用.
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