Novel and efficient synthesis of 4-indazolyl-1,3,4-trisubstituted pyrazole derivatives

Article abstract of DOI:10.1080/00397911.2013.862724

In the present study, 1-(4,5-dihydro-3,6-dimethyl-4-(1,3-diphenyl-1H- pyrazol-4-yl)-3aH-indazol-5-yl)methanone derivatives (9-12) and isoxazoleyl (13-16) have been synthesized by the condensation of 1,3-diphenyl-1H-pyrazole-4- carbaldehyde (1-4) with acetyl acetone via Knoevenagel/Michael/aldol reactions in a sequential manner to yield intermediate cyclohexanone (5-8). The intermediates (5-8) treated with NH₂NH₂·H ₂O/NH₂OH·HCl afforded 4-indazolyl-1,3,4- trisubstituted pyrazole and isoxazoleyl derivatives. All of these compounds are reported for the first time, and the structures of these compounds were confirmed by means of infrared, ¹H NMR, ¹³C NMR, and mass spectroscopy.