Synthesis, photochromism properties of a hybrid diarylethene with hydroxyl group

Abstract

An unsymmetrical diarylethene derivative 1-(2,5-dimethyl-3-thienyl)-2-[2-methyl-5-(4-hydroxylphenyl)-3-thienyl]hexafluorocyclopentene (1a) was synthesized. At the same time, its photochromic properties and fluorescence switch were investigated in detail. The results showed that this compound exhibited reversible photochromism, undergoing reversible cyclization and cycloreversion reactions upon alternating irradiation with UV and visible light both in solution and in PMMA film, and its absorption maxima were observed at 547 nm in hexane and at 554 nm in PMMA amorphous film, respectively, upon irradiation with 297 nm UV light. The fluorescence intensity of diarylethene decreased dramatically along with the photochromism from open-ring isomer to closed-ring isomer upon irradiation with 297 nm UV light in hexane. In hexane the open-ring isomer of the diarylethene 1 exhibited relatively fluorescence at 507 nm when excited at 375 nm. This new photochromic compound also exhibited remarkable optical storage character.

Photochromic and luminescence properties of a hybrid compound based on indoline spiropyran of the coumarin type and azomethinocoumarin

“…Different fluorescence emissions from the initial Fig. 9 Absorption spectra (1-3), fluorescence spectra at λ ex = 373 nm (4, 5), λ ex = 590 nm (6, 7), 340 nm (9), 470 nm (11); fluorescence excitation spectrum at λ reg = 660 nm (8) and λ reg = 550 nm (10) before (1,4,6,(9)(10)(11) and after UV irradiation with an external source of high intensity (2,5,7,8), and after relaxation in the dark (3) for (1) in ethanol solution.…”

“…In recent years, hybrid photochromic compounds have been widely studied due to their properties, which can be attractive for practical purposes such as the development of a new generation of materials for molecular electronicsmolecular switching devices, molecular logic gates, dynamic chemo-and biosensors, etc. [1][2][3][4][5][6][7][8][9][10] The important feature required for the design of such systems is a different photochemical behavior of the constituent elements implying the sensitivity to the excitation wavelength and the molecular environment.…”