Synthesis and application of metal complex dyes derived from 5-arylazo-4-hydroxy-2-phenylpyridazin-3-one

142-144Six monoazo metal complex dyes (VIII a-c and IX a-c) were derived from 5-arylazo-4-hydroxy-2-phenylpyridazine-3-ones (VI and VII) respectively and their dyeing performance on wool fibres was assessed. The compounds VI and VII were obtained by the diazotisation of 5-amino-4-chloro-2-phenylpyridazin-3-one (IV) and its coupling with gamma acid and schaffer's acid respectively. The key compound IV was prepared by the ammonolysis of 4.5-dichloro-2-phenylpyridazin-3-one (III) which was obtained by the condensation of phenylhydrazin (I) and mucochloric acid (II). The metal complex dyes when applied on wool fibres gave reddish violet to brown shades with excellent pick-up, light fastness and wash fastness