الفهرس | Only 14 pages are availabe for public view |
Abstract Azo compounds have for great many years occupied dominant position in the field of colouring matters due to their versitility. Azo dyes containing at least one (N=N) sturcture in a molecule, are the most important group of disperse dyes , and globaly comprise over 50 percent of disperse dyes because of its strong tinctorial strength compared to anthraquinone dyes, ease to make and a low cost of manufacture. Azo dyes have a vivid colour in the yellow to blue green region because of varying azo components with electronwithdrawing groups and coupling components with electronwithdrawing groups. Among these, azo dyes using heterocyclic amines have become important as they give brighter and stronger results than these based on aniline -based diazo compounds . Disperse dyes are organic colours with less water solubility, so they are applied in colloidal aqueous dispersions to hydrophobic textile fibres in which the dyes dissolve and produce the desired coloration In continuation of our interest in the synthesis of pyrazolopyridine , this work reports the synthesis of some arylazo naphthol and coupling products of active methylene compounds using a conventional method. First, amild oxidation of pyrazolopyridine by Selenium dioxide give compound 13. Then the compound 13 was reacted with malononitrile in ethanol to give compound 14. |