Temperature-Controlled Divergent Synthesis of Pyrazoles and 1-Tosyl-1 H-pyrazoles under Transition-Metal-Catalyst- and Oxidant-Free Conditions

Kai Wang; Wenjing Xu; Chengcai Xia; Xianting Cao

doi:10.3390/molecules29081706

Temperature-Controlled Divergent Synthesis of Pyrazoles and 1-Tosyl-1 H-pyrazoles under Transition-Metal-Catalyst- and Oxidant-Free Conditions

Molecules. 2024 Apr 10;29(8):1706. doi: 10.3390/molecules29081706.

Authors

Kai Wang¹, Wenjing Xu¹, Chengcai Xia², Xianting Cao¹

Affiliations

¹ College of Medical Engineering & The Key Laboratory for Medical Functional Nanomaterials, Jining Medical University, Jining 272067, China.
² Institute of Pharmacology, Pharmacy College, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan 271016, China.

Abstract

Herein, a general and practical temperature-controlled approach for the divergent synthesis of pyrazoles and 1-tosyl-1H-pyrazoles via electrophilic cyclization in the absence of transition-metal catalysts and oxidants was developed. The desired products were obtained in moderate to excellent yields from common starting materials in both ionic liquids and ethanol by simply tuning the reaction temperature. This strategy employs easily synthesized substrates, mild reaction conditions, and excellent functional-group tolerance.

Keywords: divergent synthesis; green strategies; ionic liquids; pyrazole derivatives; temperature-controlled.

Grants and funding

This work was supported by the Natural Science Foundation of Shandong Province (ZR2022QB125), the High-level Scientific Research Projects Cultivation Program of Jining Medical University (JYGC2023KJ011), the Shandong Medical and Health Science and Technology Development Plan Project (202013050376) and the Academic Promotion Programme of Shandong First Medical University (2019LJ003).