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Cl2 ⋅- 介导惰性C-H键直接和选择性转化为化物/类

Qinhua Zhang¹, Bo An¹, Yu Lei²

¹State Key Laboratory of Heavy Oil Processing, Institute of New Energy, College of Chemical Engineering, China University of Petroleum (East China), Qingdao, 266580, P. R. China.

Angewandte Chemie (International ed. in English)

|July 6, 2023

概括

研究人员开发了一种使用二基离子 (Cl2•−) 激活惰性C(sp3) -H键的新方法,产生有价值的氧化产物,如高选择性和高效的和.

科学领域:

有机化学有机化学
材料科学材料科学材料科学
光催化作用的光催化

背景情况:

为了选择性氧化,激活惰性碳- (C-H) 键,特别是C ((sp3) -H,仍然是合成化学的一个重大挑战.
现有的方法经常与选择性作斗争,导致过度氧化或不必要的副产品,阻碍了有价值的氧化化合物的高效合成.

研究的目的:

开发一种新的光催化系统,用于选择性激活C(sp3) -H键.
使用分子氧来实现C-H键的高效转化为化物和类.
探索新型反应物种在克服C-H键功能化的动力限制中的作用.

主要方法:

合成三酸结合有机聚合物作为光催化剂.
在分子氧的存在下,C-H键的光激活,产生反应性氧物种 (O2,H2O2,⋅OH).
研究二基离子 (Cl2•−) 对于C-H键激活的生成和反应性.
在酸性溶液中使用集成的两相系统来优化反应并抑制过氧化.

主要成果:

该研究确定了二基离子 (Cl2•−) 作为激活C(sp3) -H键的高效物种,其性能优于基 (Cl⋅).
实现了二化与单化运动速率比率的2000倍增加,克服了传统的运动约束.
不稳定的二化中间体很容易被化成化物或,避免化副产品的形成.
在将多转化为甲时,实现了16.94 mmol/g/h的转化率和99.5%的选择性.

结论:

这项工作提出了一种简单有效的光催化方法,用于选择性地将惰性C(sp3) -H键转化为有价值的氧化产品.
通过三酸结合聚合物生成的Cl2•−的使用为可持续化学合成提供了一个有前途的战略.
集成的两相系统有效地控制了反应,提高了产量和选择性,同时最大限度地减少了副作用.

关键词:

C−H 激活方式氧气氧气是一种光催化作用的光催化激进分子激进分子三酸盐是一种三酸盐.

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