Crown-containing styryl dyes

Ushakov, Evgeny N.; Gromov, S. P.; Федорова, О. А.; Алфимов, М. В.

doi:10.1007/bf02495396

Cited by 26 publications

(25 citation statements)

References 10 publications

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“…On passing from phenylazacrown-containing to benzocrown-containing CSD, the stability constants for complexation with alkaline-earth metal cations are known to increase by approximately two orders of magnitude [13]. It appeared of interest to develop a synthesis and to study the structural, spectral, and complex-forming properties of a new series of butadienyl dyes containing a benzocrown fragment.…”

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confidence: 99%

Synthesis, Structure, Spectroscopic Studies, and Complexation of Novel Crown Ether Butadienyl Dyes

Gromov¹,

Ведерников²,

Ushakov³

et al. 2002

HCA

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Dedicated to Professor Andre¬ M. Braun on the occasion of his 60th birthday Butadienyl dyes of the benzothiazole series with various fragments of benzocrown ethers 1a ± c were synthesized for the first time. The structures and spectral properties of crown-containing butadienyl dyes and their complexes with alkali and alkaline-earth metal cations were studied by X-ray diffraction analysis and 1 H-NMR, UV/VIS, and resonance Raman spectroscopy. To interpret the experimental results, quantumchemical calculations were performed. In the case of Sr 2 and Ba 2 ions, the formation of strong sandwich complexes [M(1b) 2 ] 2 of an unusual structure involving stacking interactions was established; the dye molecules are arranged one above another in the complex according to the −head-to-head× pattern.

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confidence: 99%

Synthesis, Structure, Spectroscopic Studies, and Complexation of Novel Crown Ether Butadienyl Dyes

Gromov¹,

Ведерников²,

Ushakov³

et al. 2002

HCA

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“…This increases the fluorescence efficiency, which manifests itself as a complexation induced fluorescence enhance ment, in agreement with the experimental data. 2 Absorption spectra of dyes 1a and 1b and their com plexes with alkali and alkaline earth cations. Previously, 15, 16 we characterized the axial and equatorial conformers of free crown ethers and their complexes by not only mutual arrangement of the aromatic ring and the RMS plane of the crown ether, but also some other geometric param eters.…”

Section: Resultsmentioning

confidence: 99%

“…Examples of the calculated spectra of dye 1a (1) and its complex with Ca 2+(2,3) represented by the sum of the Gaussian broadened peaks: conformers of the free dye perchlorate (1), axial conformers of 1a•Ca 2+ monoperchlorate(2), and equatorial conformers of the same complex (3…”

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Recoordination of a metal ion in the cavity of a crown compound: a theoretical study

et al. 2008

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The absorption spectra of styrylbenzothiazolium dye derivatives were calculated by the time dependent density functional (TD DFT) method. The dyes of interest were (p dimethylamino)styrylbenzothiazolium dye and its protonated form as well as aza 15(18) crown 5(6) containing dyes and their complexes with alkali (K + and Na + ) and alkaline earth (Ca 2+ , Sr 2+ , and Ba 2+ ) cations. Several low lying conformers of the azacrown containing dyes were considered. The electronic and geometric structures of the excited states responsible for the appearance of the long wave (π-π*) absorption bands are studied. Complexation causes a hypsochromic shift of the long wave absorption band correlating with the pyramidality of the crown ether nitrogen in the complex. The interaction of the cation with 3-4 solvent molecules or a counterion (ClO 4 -) considerably reduces this shift, especially in the conformers without the metal-nitrogen bond. In some cases, the long wave absorption band is close to the absorption band of the free dye. Similar results were obtained using the polarizable continuum model of solvation. Excited state structures of the free model dye and the free azacrown containing dyes exhibit a tendency to bond alternation. Conversely, the cationic complexes of the crown containing dyes and the protonated model dye exhibit a tendency to bond equaliza tion in the excited state. The changes in the excited state geometries of the free dyes and their complexes account for the complexation induced fluorescence enhancement observed in the experiments.

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“…[5][6][7][8][9][10][11] Compounds 3 and 4 are representatives of the crown-containing styryl dyes that show negative ionochromism. [6,7] The N-methylazacrown fragment in 4 proved to be better preorganized for binding of metal ions than the N-phenylazacrown fragment in 3. As a result, complexes of 4 with alkali and alkaline earth metal ions are characterized by much higher thermodynamic stability as compared to the corresponding complexes of 3 (for example, the lgK values for 4·Ca 2+ and 3·Ca 2+ in MeCN are about 5.2 and 2.4 respectively).…”

Section: Donor-acceptor Chromoionophoresmentioning

confidence: 99%