铜 (I) /TEMPO催化有氧酒精氧化的机制
Jessica M Hoover1, Bradford L Ryland, Shannon S Stahl
1Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, USA.
Journal of the American Chemical Society
|January 16, 2013
概括
这项研究研究了用于有氧酒精氧化的铜/TEMPO催化剂系统. 该机制揭示了基与阿利法醇的明显速度限制步骤,为催化剂设计提供了洞察力.
科学领域:
- 催化剂是一种催化剂.
- 有机化学 有机化学
- 氧化反应 氧化反应
背景情况:
- 均的铜/TEMPO (2,2,6,6-四甲基胺-N-oxyl) 催化剂对于有氧酒精氧化是有效的.
- 之前报告的一种 (bpy) Cu(I) /TEMPO/NMI (N-methylimidazole) 系统显示了高率和选择性,即使对于未激活的酒精.
研究的目的:
- 为了对 (bpy) Cu(I) /TEMPO/NMI催化剂系统进行机械研究.
- 为了比较基醇和基醇的反应性和机械路径.
主要方法:
- 使用气体吸收和in situ红外光谱学进行动力分析.
- 通过EPR和紫外线可见光谱学进行催化剂物种化表征.
- 对动态同位素效应的评估.
主要成果:
- 阐明了两阶段的催化机制:催化剂被O2氧化和基质氧化.
- 催化剂氧化过程涉及一个双核Cu(2) O(2) 中间体.
- 基质氧化通过Cu(II) 和TEMPO氧基进行,涉及一个Cu(II) -氧化物中间体.
结论:
- 基醇和基醇氧化表现出不同的周转限制步骤.
- 催化剂被O2氧化是醇的速度限制.
- 多个步骤有助于阿里法醇氧化的周转率.
相关概念视频
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