الفهرس 
الغلافيوجد فقط 14 صفحة متاحة للعرض العام
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المستخلص
Disperse azo dyes based on pyrazole system has been ~orted to have good dyeing power and fastness properties [len applied on hyDROPhobic fibers especially polyester
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mthesis and evaluation of heterocyclic azo dyes with etter fastness properties. This study deals with the reparation, characterization and evaluation of some new Ilonoazo disperse dyes based on pyrazolenucleus.
We here in report a novel route to the synthesis of ~yrazole azo (hydrazine) dyes and a study of their dyeing properties, The scopes and limitation of the new procedure for the synthesis of the novel dyestuff are also reported.
Thus, it has been found that 4-amino-2,3-dimethyl-l¬phenylpyrazolin-S-one 1 reacted with hydrochloric acid and sodium nitrite at room temperature to give the corresponding diazonium salt 2. Coupling of the latter with cyanoacetanilde derivatives 3 leads to the azo (hydrazone) derivatives 4. It was readily established that they had the hydrazone structures on the basis of both their I.R spectra, which revealed in each case a highly conjugated C=N band, and their IH NMR spectra indicated the absence of a CH signal expected for the azo form. The structure of 4a-m were established on the basis of heir elemental analysis and spectral data (IR, ’H NMR and MS). The analytical data for 4 revealed molecular fonnula in consistent with their expected structure. The IH NMR spectrum revealed two bands at 0:::2.43-3.400 ppm assignable to two CH3 groups, a
C’ ’7 {\Q _7 ”g nnm assigned to