Synthesis and spectroscopic studies of novel photochromic benzodithiacrown ethers and their complexes

Abstract

New styryl dyes containing the benzodithia-18-crown-6 fragment have been synthesized and their photoisomerization reactions and complexes with Hg2+ and Ag + cations have been investigated by steady-state electronic and resonance Raman spectroscopy. (4-Formy1benzo)dithia-18-crown-6, N-carboxypropyl-and N-carboxybutyl-2-methylbenzothiazolium bromides have also been prepared as intermediates for the styryl dye syntheses. Changes in vibrational resonance Raman spectra observed on complexation with Agf and HgZf cations or on variation of solvent polarity have been correlated with changes in the UV-VIS absorption maxima of the dyes. Preliminary assignments of the observed Raman bands to particular vibrations are made.

Crown‐ether and azobenzene‐containing liquid crystalline polymers: An influence of macromolecular architecture on optical properties and photo‐orientation processes

“…Introduction of a potassium cation in crown ether “cavity” draws off electron density from the oxygen atoms and, thus, shifts the absorbance peak to the short‐wavelength spectral range. A similar effect was demonstrated for the low molar mass crown ether‐containing dyes 13, 28…”

“…A similar effect was demonstrated for the low molar mass crown ether-containing dyes. 13,28 Photo-orientation Process in Thin Films of the Homopolymers Irradiation of thin polymer films by blue polarized laser light (473 nm) causes the photoinduced orientation of the side groups in a direction perpendicular to the polarization direction. This process is accompanied by the growth of linear dichroism (eq 1 and Fig.…”

Structure and ion-complexing properties of an aza-15-crown-5 ether dye: synthesis, crystallography, NMR spectroscopy, spectrophotometry and potentiometry

“…Secondly, the conformational changes within the crown moiety upon complex formation may modify the ring-current effects from the adjacent phenyl group on the H(1,10) methylene protons, resulting in an upfield shift. The crystal XRD data and the NOESY spectra indicate that the distances between the H(1,10) and H(2,9) methylene protons and the H (16,18) phenyl protons in non-complexed 3 are equal. In contrast, the NOESY spectra indicate that the H(1,10) methylene protons are closer to the H (16,18) protons in the complexed form, resulting in a stronger interaction than that between the H(2,9) and H (16,18) protons.…”

Novel styrylbenzothiazolium dye-based sensor for mercury, cyanide and hydroxide ions

“…By the careful design of the ionic binding unit conjugated with the styryl dye, some hemicyanine dye-based chemosensors have been recently developed that use ICT signaling mechanisms. For example, a styrylbenzothiazolium dye with a crown ether as a binding unit was developed for Mg 2+ [13], Ag + , Hg 2+ [14] and Ba 2+ [15] sensing. Boronic acid-grafted styryl pyridinium dyes have been used as cyanide fluorogenic chemosensors [16].…”