International Journal of ChemTech Research CODEN( USA): IJCRGG ISSN : 0974-4290 Vol.6, No.1, pp 719-729, Jan-March 2014 Pyridazine and its related compounds: Part 26. [1] Synthesis and Application of some Monoazo disperse dyes derived from 3-hydrazinopyridazine A. Deeb٭, F. Yassine, N. Aouf, and W. Shehta Chemistry Department, Faculty of Science, Zagazig University, Zagazig, Egypt. ٭Corres.author: dralideeb@hotmail.com Abstract: 3-Hydrazine-4,5,6-triphenylpyridazine was used as key intermediate for synthesis of 3-(4-arylazo- 3,5-disubstituted pyrazol-1-yl)-4,5,6-triphenylpyridazines. Some of the dyes produced were applied to polyester as disperse dyes, and their color, and fastness properties were evaluated. Keywords: 3-(Pyrazol-1-yl)pyridazine. Azodispersed dyes, Polyester fabrics. Color measurements. Fastness properties. Introduction Derivatives of the pyridazine ring systems are known to possess potent biological and pharmacological properties. [2-4] On the other hand some pyrazole derivatives are very important class of heterocycles due to their biological and pharmacological activities. [5] Also, they are used as key starting material for the synthesis of commercial aryl/hetarylazopyrazole dyes. [6] All these properties aroused our interest in synthesing new heterocyclic compounds including the pyridazine moiety which is a continuation of our previous work. [7,8] The present investigation deals with the synthesis of some 3-[4-arylazo-3,5-disubstituted pyrazol-1-yl]-4,5,6- triphenylpyridazine and 4-arylazo-3-methyl-1-(4,5,6-triphenylpyridazin-3-yl)-1H-pyrazol-5-ol dyes from 3- hydrazino-4,5,6-triphenylpyridazine and an evaluation of their properties on polyester fabric. Results and Discussion Coupling of active methyl compounds such as acetylacetone and malononitrile with various aryldiazonium chlorides in sodium acetate buffered solution afforded the corresponding azobenzene acetyacetone and azobenzenemalononitrile derivatives 2a-e and 2f-g in good yield, respectively (Scheme 1). Spectral data for such compounds indicate them to have a hydrazone configuration, [9] caracterisation and spectral data for compounds 2a-j were described in the previous part. [10] htm . framesphinxsaichemtech / com . sphinxsai . www :// http