Effect of the chromophoric unit on the complex formation properties in the crown ether containing styryl dyes

The Effect of Alkyl Substituent Length on Receptor Properties of Dithiaaza-Сrown-Hemicyanine MonolayersThe Effect of Alkyl Substituent Length on Receptor Properties of Dithiaaza-crown - Hemicyanine Monolayers

“…[1][2][3][4] From this standpoint, crown ether substituted fluoro-and chromophores capable of significant changes of photophysical properties upon selective binding of cations are of special interest. [5][6][7][8][9][10][11] Modification of the crown ether cycle allows achieving high selectivity and binding constants for biologically and environmentally important metal ions. For example, replacement of one or two oxygen atoms in this cycle by sulfur ones can lead to higher affinity for mercury and copper cations.…”

“…[12][13][14][15][16][17][18] Moreover, simultaneous inclusion of nitrogen atom into the crown-substituent of a coloured molecule as a part of both ionophoric and chromophoric moieties is an easy way to impart the chromoionophoric power to the dye molecule and obtain a spectral response to metal cation binding since their interaction with the nitrogen atom will reduce the overall chromophore conjugation and thus change the photophysical properties of the system. [5][6][7][8][9][10][11][19][20][21][22][23] In this regard, aza-crown substituted hemicyanines represent one of the most promising compounds for sensory applications due to the combination of hemicyanine spectral properties (absorbance and fluorescence in visible range), crown ether receptor ability and ease of chemical modification. [5,12,17,[24][25][26][27][28][29][30][31][32] However, most studies concerning the sensory properties of such crown-substituted hemicyanines were done in solution.…”