Copper-catalyzed selective oxidation of hydrazones through C(sp3)-H functionalization
Jiabin Shen1,2, Xiaoying Jiang2,3, Haifeng Wu1,2
1Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, China. zhuq@zjut.edu.cn.
Organic & Biomolecular Chemistry
|October 7, 2021
Summary
A new copper-catalyzed method efficiently oxidizes hydrazones at the alpha-position. This provides a convenient synthesis for carbonyl hydrazones with broad substrate compatibility and good yields.
Area of Science:
- Organic Chemistry
- Catalysis
- Synthetic Methodology
Background:
- Hydrazones are versatile synthetic intermediates.
- Oxidation reactions are crucial for functional group transformations.
- Efficient synthesis of carbonyl hydrazones remains an area of interest.
Purpose of the Study:
- To develop a simple and mild protocol for the copper-catalyzed oxidation of hydrazones.
- To explore the synthesis of carbonyl hydrazones via α-oxidation.
- To investigate the scope and limitations of the developed method.
Main Methods:
- Copper-catalyzed oxidation reaction.
- Utilized various hydrazone substrates.
- Purification and characterization of products.
Main Results:
- Successfully achieved copper-catalyzed oxidation of hydrazones at the α-position.
- Obtained corresponding carbonyl hydrazone products in moderate to good yields.
- Demonstrated compatibility with a variety of substrates.
Conclusions:
- The reported protocol offers an efficient and convenient method for synthesizing carbonyl hydrazones.
- A free radical pathway mechanism is proposed for the observed transformation.
- This work expands the synthetic utility of hydrazones.
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