A series of pyrazole-based heteroaromatic compounds were synthesized by the reaction of 3-methyl-5-pyrazolone and aromatic aldehydes in Choline chloride/urea DES as a green solvent. This simple and green procedure has advantages such as easy operation, short reaction times, efficient yields, low cost and minimum use of hazardous solvents and catalysts. The structure of compounds was determined by IR, 1H and 13C NMR spectra, and the crystal structure of 4a was confirmed using X-ray crystallographic analysis. The optical properties of Pyrazole derivatives 4a-g have also been studied with UV/vis and fluorescence spectroscopy. All of these pyrazole-containing heteroaromatic compounds displayed maximum emission peak from 340 to 360 nm.

通过3-甲基-5-吡唑酮与芳香醛在胆碱氯化物/脲DES中作为绿色溶剂反应，合成了一系列吡唑基杂芳族化合物。这种简单而绿色的程序具有操作简便，反应时间短，产率高，成本低以及有害溶剂和催化剂使用量少等优点。通过IR，1 H和13 C NMR光谱确定化合物的结构，并通过X射线晶体学分析确认4a的晶体结构。吡唑衍生物4a-g的光学性质也已经用UV / vis和荧光光谱法研究。所有这些含吡唑的杂芳族化合物均显示出从340至360 nm的最大发射峰。