Study the synthesis and fluorescent properties of a new series of D‐π‐A fluorescent dyes based on nicotinonitrile and azobenzene is the main objective for this work. Reduction with Zn/HCl, diazotization with HCl/NaNO₂, and coupling using catalytic NaOH or AcONa are simple applied methods. Where, nicotinonitrile 3 was synthesized via reduction of nitro derivative 1 followed by diazotization with HCl/NaNO₂ in acetic acid. The formed benzene diazonium chloride was coupled with several activated phenols, aniline, and α‐CH acids to yield the respective azo dyes 4‐11 in moderate to good yield. Dyes 11a‐d subjected to intermolecular cyclization with hydrazine hydrate resulted in pyrazole dyes 12‐15 in moderate yield. Dyes containing pyrazole moiety or electron‐withdrawing groups at the sixth position of pyridine nucleus exhibit stronger blue‐green emission (λ _fl.max = 503, 507, 500, 501, 502, 493, and 514 nm) than that of the rest of compounds.

中文翻译：

---

基于烟腈和偶氮苯衍生物的D-π-A荧光染料的设计与合成

研究基于烟腈和偶氮苯的一系列新的D-π-A荧光染料的合成和荧光性质是这项工作的主要目标。用Zn / HCl还原，用HCl / NaNO ₂重氮化以及使用催化NaOH或AcONa偶联是简单应用的方法。其中，通过还原硝基衍生物1，然后在乙酸中用HCl / NaNO ₂重氮化，来合成烟腈3。将生成的苯重氮氯化物与几种活化的酚，苯胺和α-CH酸偶合，以中等至良好的产率产生相应的偶氮染料4-11。染料11a-d用水合肼进行分子间环化后，吡咯染料12-15的产量适中。含有吡唑部分或吸电子基团在吡啶环的第六位置染料显示强的蓝绿色发光（λ _fl.max比其余的503 = 507，500，501，502，493，和514纳米）化合物。