在空气条件下对Cu (II) -Arenes和酸之间的催化氧化交叉合反应进行机制研究
Qian Zhang1, Yang Liu1, Ting Wang2
1MOE Key Laboratory of Bioorganic Phosphorous Chemistry and Chemical Biology, Department of Chemistry , Tsinghua University , Beijing 100084 , China.
Journal of the American Chemical Society
|April 10, 2018
概括
这项研究表明,铜 (II) 是铜催化交叉合反应的关键中间体,而不是铜 (III). 了解这种机制有助于设计新的铜催化反应.
科学领域:
- 有机金属化学
- 催化剂
- 有机合成
背景情况:
- 在催化过程中,铜盐是贵金属的丰富,廉价,少毒的替代品.
- 铜催化反应广泛用于C-C和C-原子键的形成,但它们的机制尚不清楚.
- Azacalix[1]arene[3]pyridine宏循环为机理学研究提供了明确的铜 (II) 和铜 (III) 复合体.
研究的目的:
- 用空气作为氧化剂来阐明Cu (II) 催化氧化交叉合的反应机制.
- 确定参与催化循环的有机金属中间体.
- 为新的铜催化反应提供理性设计的见解.
主要方法:
- 与酸结石测量反应.
- 光谱技术:XPS,EPR,1H NMR,HRMS,紫外线
- 产品和铜种的分离和量化.
- 电子结构和能量学的计算分析.
主要成果:
- 铜 (II) 被确定为反应性中间体,而不是铜 (III).
- 拟议的机制包括电友性化,转化,形成Cu (III) 和Cu (I) 的氧化还原反应以及还原性消除.
- (I) 种被氧气重新氧化为 (II),为下一个循环再生催化剂.
结论:
- 在交叉合反应中,铜 (II) 化合物的反应性已得到澄清.
- 已经提出了Cu (II) 催化氧化交叉合的详细催化循环.
- 这种机理学理解对于开发新的铜催化合成方法很有价值.
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