Saeed Aamer, Shabir Ghulam
Department of Chemistry, Quaid-I-Azam University, Islamabad 45320, Pakistan.
Department of Chemistry, Quaid-I-Azam University, Islamabad 45320, Pakistan.
Spectrochim Acta A Mol Biomol Spectrosc. 2014 Dec 10;133:7-12. doi: 10.1016/j.saa.2014.04.171. Epub 2014 May 15.
Five phenolic azo-dyes (3a-e) were synthesized by diazo coupling of the suitably substituted anilines (1a-e) with phenol at low temperature in alkaline medium. The resulting dyes have low solubility in aqueous medium due to lack of carboxylic or sulfonic solubilizing functionalities. The hybridization of perylene dianhydride with phenolic azo-dyes was achieved by the nucleophilic aromatic substitution (SNAr) reaction of perylene-3,4,9,10-dianhydride 4 with phenolic azo-dyes 3a-e in basic medium. The hybrid dyes exhibit absorption maxima λmax in the range 440-460nm in aqueous medium due to presence of azo linkage and highly conjugated system of π bonds. Fluorescence spectra of these dyes in water show sharp emission peaks with small band widths. The structures of perylene-azo dyes were confirmed by FTIR and NMR spectroscopy.
通过在碱性介质中低温下将适当取代的苯胺（1a - e）与苯酚进行重氮偶合反应，合成了五种酚醛偶氮染料（3a - e）。由于缺乏羧酸或磺酸增溶官能团，所得染料在水性介质中的溶解度较低。通过在碱性介质中使苝 - 3,4,9,10 - 二酐4与酚醛偶氮染料3a - e发生亲核芳香取代（SNAr）反应，实现了苝二酐与酚醛偶氮染料的杂化。由于存在偶氮键和高度共轭的π键体系，杂化染料在水性介质中的吸收最大值λmax在440 - 460nm范围内。这些染料在水中的荧光光谱显示出具有小带宽的尖锐发射峰。苝 - 偶氮染料的结构通过FTIR和NMR光谱得到证实。
