AlCl3-Catalyzed diazocoupling of 1-(aryl/hetaryl)-3-phenyl-1H-pyrazol-2-in-5-ones in aqueous medium. Synthesis of hetaryl-azopyrazolones and their application as disperse dyes

Organic synthesis in water is a new methodology of green chemistry. AlCl3-catalyzed diazocoupling of 1-(aryl/hetaryl)-3-phenyl-1H-pyrazol-2-in-5-ones (1) in water with different aryl/hetaryldiazonium salts afforded the corresponding hetaryl-azopyrazolones (2) as colored products with high yields. These dyes were characterized by UV–vis, FT-IR and 1H NMR spectroscopic techniques and elemental analysis. Cotton, wool, silk and polyesters fabrics were dyed and their photostability and color fastness were identified.