Details

Autor(en) / Beteiligte

• Zhukova, Yuliya
• Studenyak, Yaroslav
• Mariychuk, Ruslan
• Snigur, Denys

Titel

Thermosolvatochromic Behavior of Quinolinium and Pyridinium 4-Hydroxystyryl Dyes in Solutions

Ist Teil von

• Journal of solution chemistry, 2023-08, Vol.52 (8), p.870-880

Ort / Verlag

New York: Springer US

Erscheinungsjahr

2023

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• In the current study a number of 4-hydroxystyryl dyes (4-HSD), 4-[-2-(4-hydroxy-3-methoxyphenyl)vinyl]-1-octylpyridinium bromide (4OP-MS) and 2-[2-(3,5-dimethyl-4-hydroxystyryl)]-1-methylquinoline iodide (2MQ-DMS), were synthesized and characterized using NMR, IR and Raman spectroscopy methods. The solvatochromic and thermochromic properties of their merocyanine form in solutions (water, ethanol, propanol-2, butanol-1) were observed and studied via UV–Vis spectrophotometry and tristimulus colorimetry methods. The sensitivity of the studied representatives to temperature changes in the range of 20.0–70.0 °C showed opposite thermochromic effects in solutions. Thus, the 4OP-MS shows a bathochromic shift of the spectrum (up to 17 nm) with increasing temperature and a significant increase in intensity in alcohol media (up to 3.5%—without taking into account the thermal expansion of the solvent). Under similar conditions, the 2MQ-DMS shows a significant decrease in intensity, which reaches 44% in the case of butanol, with practically no shifts in the light absorption maximum with temperature. When passing from aqueous to propanol-2 solutions, the thermosolvatochromic effect in the case of 4OP-MS increases slightly from 108 to 113 nm with an increase in temperature by 50.0 °C, and for 2MQ-DMS, on the contrary, it decreases from 64 to 48 nm. These effects indicate, on the one hand, the possibility of using such dyes to create liquid thermochromic systems, and on the other hand, the need to take them into account when creating and using molecular optical sensors.