Pyridazine derivatives and related compounds. 23*. Synthesis of 3-substituted pyrazolo[3,4-c]pyridazines and their application as disperse dyes

Abstract

Acetylacetone and malononitrile were coupled with diazotized arylamines to give arylazoacetyl-acetones and arylazomalononitriles. When refluxed with 3-hydrazino-4,5-diphenyl-1H-pyrazolo-[3,4-c]pyridazine in the presence of ethanol/HCl, they yielded the corresponding 3-[4-(arylazo)-3,5-di-methylpyrazol-1-yl]- and 3-[3,5-diamino-4-(arylazo)pyrazol-1-yl]-4,5-diphenyl-1H-pyrazolo[3,4-c]pyri-dazine dyes. The dyes were applied to polyester and polyamide fabrics, and their spectral and fastness properties were measured.