Abstract: By using 2, 3-epoxypropan-1-one and arylhydrazine, trimethylamine-promoted in situ ring opening/cyclization reaction at100 ℃ was developed in ethanol under microwave irradiation, affording a series of triarylpyrazoles in good yields. Single crystal X-ray diffraction confirmed the structure of compound 3a. Furthermore, the structures of all products were characterized by infrared, nuclear magnetic, and high-resolution mass spectrometry.

Key words: 2,3-epoxypropan-1-one, arylhydrazine, triarylpyrazole