附加的易斯酸可使二氧化反应和催化氧化与Ni
Daniel M Beagan1, Carolina Rivera1, Nathaniel K Szymczak1
1University of Michigan, 930 N. University Ave., Ann Arbor, Michigan 48109, United States.
Journal of the American Chemical Society
|April 25, 2024
概括
(II) 复合物与绑定的易斯酸具有与氧的独特反应性. 较弱的易斯酸如皮纳科尔博兰稳定这些复合物,使催化原子抽象和氧原子转移反应成为可能.
科学领域:
- 有机金属化学
- 催化剂
- 易斯酸化学
背景情况:
- (II) 复合物是多用途的催化剂.
- 二次球体相互作用可以调节金属中心的反应性.
- 易斯酸可以影响过渡金属复合物的行为.
研究的目的:
- 研究连接的易斯酸对Ni (II) 复合物的反应性的影响.
- 了解酸易斯酸的氧化稳定性.
- 为这些复合物开发新的催化应用.
主要方法:
- 用不同的易斯酸合成和表征Ni (II) 复合物.
- 在现场进行紫外线光谱检测以监测反应性.
- 计算研究 (例如,DFT) 了解反应机制.
- 原子抽象和氧原子转移的催化试验.
主要成果:
- 具有强的易斯酸 (9-borabicyclo[3.3.1]nonane) 复合物与O2具有非典型的反应性.
- 在室温下进行氧化除.
- 较弱的易斯酸 (pinacolborane) 可以稳定复合物,防止氧化.
- 从中获得催化原子和向PPh3转移氧原子.
结论:
- 连接的易斯酸度显著影响Ni ((II) 复合物的稳定性和反应性.
- 仔细选择易斯酸对于控制氧化途径至关重要.
- 这些发现为开发新的Ni催化转化开辟了道路.
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