An Efficient One-Pot Synthesis of 3,5-Disubstituted 1H-Pyrazoles
Lei-Lei Wu, Yi-Cen Ge, Ting He, Lei Zhang, Xing-Li Fu, Hai-Yan Fu, Hua Chen*, Rui-Xiang Li
*Key Lab of Green Chemistry and Technology, Ministry of Education, The Institute of Homogeneous Catalysis, College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu 610064, P. R. of China, Email: scuhchenscu.edu.cn
L.-L. Wu, Y.-C. Ge, T. He, L. Zhang, X.-L. Fu, H.-Y. Fu, H. Chen, R.-X. Li, Synthesis, 2012, 44, 1577-1583.
DOI: 10.1055/s-0031-1290772 (free Supporting Information)
An efficient, general, one-pot, three-component procedure for the preparation of 3,5-disubstituted 1H-pyrazoles includes condensation of substituted aromatic aldehydes and tosylhydrazine followed by cycloaddition with terminal alkynes. The reaction tolerates various functional groups and sterically hindered substrates to afford the desired pyrazoles in good yields.
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