کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
175380 | 458909 | 2016 | 10 صفحه PDF | دانلود رایگان |
• Three sets of novel post-modification S-containing heterocyclic azo dyes are described.
• Representative crystal structures for every series are obtained and compared.
• Variation of π-conjugated length and polarity shows different λmax and solvatochromism.
• An α,β-unsaturated cyanoacetic ester has the largest bathochromic shift of 87 nm.
In order to further adjust the π-conjugated system, solubility and electronic spectrum of 2-amino-3-cyano-4-chloro-5-formylthiophene based blue colored heterocyclic blue azo dyes, a post-modification strategy has been used to extend their terminal aldehyde radical into either an imine, acetal or α,β-unsaturated cyanoacetic ester group. The resultant azo-azomethine dyes exhibit slight bathochromic shifts in their UV–Vis spectra with the increase of the π-conjugated system. In contrast, acetal terminated products display good solubility in organic solvents but hypsochromic shifts in their UV–Vis spectra. It is worth mentioning that the α,β-unsaturated cyanoacetic ester derivatives show significant bathochromic shifts and improvement of solubility simultaneously originating from the presence of increased π-conjugated system as well as the terminal cyano and ester groups. It is believed that the current study could provide a practical post-modification strategy for decorating and improving the dyeing performance of certain dyes with functional end groups.
A post-modification strategy has been achieved for 2-amino-3-cyano-4-chloro-5-formylthiophene based heterocyclic blue azo dyes with the common terminal aldehyde group, where an α,β-unsaturated cyanoacetic ester derivative shows the largest bathochromic shift of 87 nm and improvement of solubility simultaneously.Figure optionsDownload as PowerPoint slide
Journal: Dyes and Pigments - Volume 133, October 2016, Pages 143–152