Department of Chemistry, Faculty of Science, Gazi University, Yenimahalle, 06560, Ankara, Turkey.
Department of Chemistry, University of Nevada, Reno, 1664N. Virginia St, Reno, NV, 89557, USA.
Anal Sci. 2023 Jun;39(6):829-842. doi: 10.1007/s44211-023-00281-0. Epub 2023 Feb 6.
This study reports the synthesis of two novel thiazolylazo dyes (4 and 5) bearing coumarin-thiophene moiety. UV-Vis spectroscopy was used to investigate the photophysical properties of 4 and 5 in different solvents. The dyes displayed good potential for hydroxide sensing in different mediums. The reversibility was also studied, and it was found that 4 and 5 could be reverted to their original state by adding acid. Furthermore, the acidochromic properties were studied in protic and aprotic media. Both dyes displayed a good acidochromic response in DCM. Moreover, 4 and 5 were investigated for pH sensing, and it was found that both compounds displayed changes in absorption spectra in a basic media. The theoretical calculations were carried out to investigate the deprotonation and protonation mechanisms using density functional theory (DFT). The thermal properties of the dyes were investigated using thermogravimetric analysis (TGA). The results showed good thermal stability up to around 200 °C.
本研究报告了两种含有香豆素-噻吩部分的新型噻唑偶氮染料（4 和 5）的合成。通过紫外-可见光谱研究了 4 和 5 在不同溶剂中的光物理性质。这些染料在不同介质中对氢氧根离子具有良好的传感潜力。还研究了其可逆性，发现通过添加酸可以将 4 和 5 恢复到原始状态。此外，在质子性和非质子性介质中研究了酸致变色性质。两种染料在 DCM 中均显示出良好的酸致变色响应。此外，还研究了 4 和 5 对 pH 值的传感性能，发现这两种化合物在碱性介质中均显示出吸收光谱的变化。使用密度泛函理论（DFT）进行了理论计算，以研究去质子化和质子化机制。使用热重分析（TGA）研究了染料的热性能。结果表明，染料的热稳定性良好，最高可达 200°C 左右。
