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Copper-Promoted Aerobic Oxidative [3+2] Cycloaddition Reactions of N,N-Disubstituted Hydrazines with Alkynoates: Access to Substituted Pyrazoles

Xiaoying Zou, Lvyin Zheng*, Xiaoya Zhuo, Yumei Zhong, Yingying Wu, Beining Yang, Qifang He and Wei Guo*

*Key Laboratory of Organo-Pharmaceutical Chemistry of Jiangxi Province, Gannan Normal University, Ganzhou 341000, China, Email:,

X. Zou, L. Zheng, X. Zhuo, Y. Zhong, Y. Wu, B. Yang, Q. He, W. Guo, J. Org. Chem., 2023, 88, 2190-2206.

DOI: 10.1021/acs.joc.2c02610

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A copper-promoted aerobic oxidative [3+2] cycloaddition of N,N-disubstituted hydrazines with alkynoates provides various substituted pyrazoles in good yields in the presence of a base. In this method, inexpensive Cu2O serves as the promoter and air acts as the green oxidant. This convenient reaction exhibits high atom,  step economy, and regioselectivity.

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proposed mechanism

Key Words

Pyrazoles, Air

ID: J42-Y2023