Synthesis and spectral properties of malononitrile-based merocyanine dyes

Kulinich, A. V.; Derevyanko, N. A.; Ishchenko, A. A.

doi:10.1007/s11172-006-0196-0

Cited by 35 publications

(24 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Symmetrical polymethine dyes 1 b and 2 are characterized by negative solvatochromism, whereas merocyanine 3 b , similarly to 3 a , should be positively solvatochromic . Yet for all three dyes, interaction with DND results in a bathochromic shift of the absorption and fluorescence bands.…”

Section: Resultsmentioning

confidence: 98%

See 1 more Smart Citation

Interaction of Polymethine Dyes with Detonation Nanodiamonds

et al. 2019

View full text Add to dashboard Cite

Among cationic, anionic, and merocyanine polymethine dyes, the binding to detonation nanodiamond (DND) colloid particles in hydrosol occurs only for negatively charged dye species. This, in view of the positive ζ‐potential of the DND used in this study, suggests the predominance of electrostatic interactions over other intermolecular forces in such systems. Indeed, after decorating the merocyanine and the cationic dye by one and two negatively charged sulfopropyl groups, respectively, so that the net charge of their colored species becomes negative, the compounds also demonstrate affinity to the DND particles. In all cases, the binding of dyes to DND is accompanied by a decrease in fluorescence intensity and a bathochromic shift of their absorption and fluorescence bands. A quantitative study of the dyes adsorption on the DND nanoparticles as performed using the Küster‐Freundlich and Langmuir equations reveals some peculiarities of their attaching to the DND aggregates and allows estimating the specific area of the DND particles at a concentration of 0.0212 wt/vol %.

show abstract

Section: Resultsmentioning

confidence: 98%

“…All studied dyes were synthesized and purified according to known procedures, at the Institute of Organic Chemistry of NAS of Ukraine. Their purity was checked using TLC and physical‐chemical methods ( 1 H NMR, UV‐Vis absorption spectroscopy).…”

Section: Methodsmentioning

confidence: 99%

Interaction of Polymethine Dyes with Detonation Nanodiamonds

et al. 2019

View full text Add to dashboard Cite

show abstract

“…The absorption band becomes narrower and more intense with increasing electron-donating ability of the second terminal nucleus. This behavior is typical of merocyanine dyes that contain weak electron-acceptor terminal nuclei [11] and is a result of an increase in the polarization of the donor-acceptor system through the increasing electron-donating properties of another nucleus, that is, the increased contribution of the mesomeric form G2. The opposite trend is observed at short wavelengths.…”

Section: Resultsmentioning

confidence: 91%

Boradipyrromethenecyanines

2009

View full text Add to dashboard Cite

A series of meso-polymethine-substituted BODIPY compounds have been synthesized by the reaction of mesomethyl-3,5-diphenylboradipyrromethene with a number of hemicyanine derivatives. The dyes obtained exhibit intense long-wavelength absorption, but weak fluorescence. Upon protonation of the dyes the long-wavelength band disappears and the intensity of the short-wavelength band in- IntroductionBoradipyrromethene dyes (4,4-difluoro-4-bora-3a,4a-diazas-indacenes, BODIPY, BDP) have attracted considerable attention over the past two decades. The ever increasing interest in this type of compound is due to their excellent thermal, chemical, and photochemical stability, high molar absorptivity, high fluorescence quantum yields, insensitivity to solvent polarity and pH, long excited-state lifetimes, a large two-photon cross-section for multiphoton excitation, lack of ionic charge, and good solubility.[1] However, the absorption maxima of the majority of BODIPYs are below 600 nm. Long-wavelength dyes are important for both basic and applied research [2] and therefore many synthetic approaches exist for modifying the BODIPY core to give structures that absorb at longer wavelengths. One of the most promising approaches to the modification of BOD-IPY is its peripheral functionalization with conjugated chromophores. Scheme 1.[a] Institute of Organic Chemistry, National Academy For example, distyryl-substituted derivatives A exhibit a bathochromic shift of the absorption maximum of 79 nm compared with diphenyl-substituted analogues (see Scheme 1). The bathochromic shift of phenylethynyl analogues B is somewhat smaller, however, both A and B are typical BODIPYs and demonstrate high fluorescence quantum yields that are fairly insensitive to the nature of the solvent.[3] The introduction of additional 4-(dialkylamino) substituents into A (structure C [4] ) results in even more pronounced spectral changes, with bathochromic shifts of around 80 nm. The structures C exhibit very small solvatochromism and considerable positive solvatofluorochromism. The fluorescence intensity increases significantly with decreasing solvent polarity. Protonation of the dialkylamino groups in C leads to optical properties that are very similar to those of A. Although the charge-separated mesomeric form C2 is typical of merocyanine dyes, the properties of the structures C (e.g., easy protonation, weak solvatochromism, and relatively low molar absorptivity) as a whole do not correspond to those of merocyanines. Thus, the dialkylamino groups in structures C provide considerable spectral changes, but do not change the color of the V. P. Yakubovskyi, M. P. Shandura, Y. P. Kovtun FULL PAPER BODIPY core. Therefore in this case they cannot be referred to as true "end groups" as defined in the ideology of polymethine dyes.This statement is even more evident for structures D. [3a,4b,5] In this case the dialkylamino group leads to a small hypsochromic shift of the BODIPY absorption maximum. The fluorescence quantum yields are quenched in polar solvents but not i...

show abstract

“…UV, λ max /nm (ε): 575 (62 120) (EtOH), 540 (61 290) (CHCl 3 ). 1 13 C NMR (DMSO d 6 ), δ: 13.9 (OCH 2 CH 3 ); 41.9 (CH 2 ); 60.9 (OCH 2 CH 3 ); 97.2 (γ C); 145.6 (β C); 155.7 (δ C). A number of signals were not accumulated because of the poor solubility of the sample.…”

Section: 5 Bis(3 Dimethylaminoprop 2 Enylidene) 1 Methylpiperi Din mentioning

confidence: 99%

“…13 C NMR spectra and the chemical shift differences Δδ of the adjacent polymethine C atoms for dyes 8b and 1b in CDCl 3 75°C for 4 h, kept for a day, and concentrated in vacuo.…”

mentioning

confidence: 99%