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A variety of new azopyrazolo [1,5‐c]‐as‐triazine dyes have been synthesised via diazotisation of 3‐amino‐4‐arylazo‐1‐pyrazolin‐5‐one and coupling with active hydrogen reagents. These dyed nylon 6, nylon 66, acrylic, polyester, silk and wool with colours ranging from scarlet red to dark brown and may find useful applications.

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A variety of new arylazopyrazole derivatives were obtained by the coupling of diazotised 5-amino-4-arylazopyrazoles with active methylene reagents and treatment of the resulting products with hydroxylamine hydrochloride. The behaviour of the newly synthesised products as acidic, direct and basic dyes on textiles is reported.

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Reaktionen mit Acetoacetanilid: Neue Synthesewege fur polyfunktionell substituierte PyridinderivateAcetoacetanilid reagiert mit Malononitril und Ethyl-cyanoacetat in Gegenwart von Natrium-ethanolat zu Pyridin-und Crotononitril-Derivaten 4 und 7.In the last few years we were interested in the synthesis of polyfunctionally substituted heterocyclic systems using readily obtainable nitriles as starting materials1.*'. In continuation of our work we investigated the reaction of malononitrile and ethyl cyanoacetate with acetoacetanilide. Ducker3' reported the Knoevenagel reaction of P-ketoanilides with malononitrile in benzene to give the dicyanomethylene compound 1. The latter on heating in basic ethanolic solution produced the pyridine 2. However, carrying out the reaction of malononitrile and acetoacetanilide in sodium ethoxide solution, a product with molecular formula CI3HllN30 was obtained. Structure 3 was established for this product based on the IR and ' H NMR spectra. The latter reveals the presence of two D,O-exchangeable protons (6 = 5.16). Furthermore, compound 3 is not identical with an authentic sample of compound 2 (m.p. and mixture m.p. and finger print region in the IR spectrum).Compound 3 coupled with benzenediazoniuni chloride to give the phenylazo derivative 4. With benzaldehyde and salicylaldehyde the corresponding azomethines 5a, b were obtained.On the other hand, the reaction of malononitrile with acetoacetanilide in ethanol containing piperidine gave two products which were separated utilising the greater solubility of one of them in boiling ethanol. The insoluble product turned out to be identical with compound 2. The other soluble product has the molecular formula ClhH13NS0 to which structure 6 was assigned, based on the 1R spectrum which shows typical and strong NH absorptions at 3250, 3360, and 3495 cm-', unconjugated nitrile bands at 2200 and 2180 cm-', and a strong carbonyl band at 1680 cm-'. The 'H NMR spectrum shows signals of two D20-exchangeable protons at 6 = 4.25 for the NH2 group, a characteristic one-proton singlet for CH(CN)2 at 6 = 6.35 and a broad multiplet for NH at F = 8.75. Compound 6 may be formed by dimerisation of malononitrile in basic medium followed by subsequent condensation with acetoacetanilide and cy~lisation~-~'.The reaction of acetoacetanilide with ethyl cyanoacetate in the presence of sodium ethoxide gave only one product of molecular formula CI5Hl6N2O3 for which structure 7 was established. Further confirmation for structure 7 is established by its identical behaviour (0 VCH Verlagsgesellschaft mbH, D