合成,结构和光谱表征和单核(III) - 氧复合物的反应性
Jaeheung Cho1, Ritimukta Sarangi, Hye Yeon Kang
1Department of Bioinspired Science, Center for Biomimetic Systems, Ewha Womans University, Seoul 120-750, Korea.
Journal of the American Chemical Society
|November 11, 2010
概括
这项研究合成和表征了 (III) - 氧复合物与四相宏环联体,揭示了它们在氧化和O (II) - 转移反应中的侧向结合和反应性,受宏环环大小的影响.
科学领域:
- 协调化学 协调化学
- 生物有机化学 生物有机化学
- 催化剂是一种催化剂.
背景情况:
- 金属-二氧化物添加物是通过金属酶和仿生系统激活二氧化物的关键中间体.
- 了解这些中间体的结构和反应性是开发高效催化剂的关键.
研究的目的:
- 为了合成和表征单核(III) - 氧复合物,具有不同的四同宏环联体环大小.
- 研究这些复合物在化氧化和O(2) 转移反应中的活性.
- 阐明宏环联体环大小对复合反应性的影响.
主要方法:
- 合成单核 (III) -氧复合物, (Co) -12-TMC (O) -2)) 和 (Co) -13-TMC (O) -2) 的合成.
- 使用光谱技术 (例如,共振拉曼) 和X射线晶体学进行表征.
- 在阿尔代氧化和O2转移到II复合物的反应性评估.
主要成果:
- 证实过氧联结物以侧面的n2方式结合,O-O键距离为1.439 Å.
- 共振拉曼光谱显示O-O键的拉伸频率为902厘米.
- 在阿尔德海德氧化和O(2) 转移中,反应性取决于宏环联体环大小,[Co(13-TMC) (((O(2)) ]](+) 的反应性高于[Co(12-TMC) (((O(2)) ](+).
结论:
- 合成的 (III) - 氧复合物作为二氧化物激活中间体的明确模型.
- 宏环联体环大小在氧化和O2转移反应中调节-复合物的反应性方面发挥着重要作用.
- 这些发现有助于了解金属酶机制和设计新的氧化催化剂.
相关概念视频
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