S 98 Synthesis, Photophysical and Redox Properties of the D-pi-A Type Pyrimidine Dyes Bearing the 9-Phenyl-9H-Carbazole Moiety [Electronic resource] / E. V. Verbitskiy [и др.] // Journal of Fluorescence. - 2015. - Vol. 25, № 3. - С. 763-775. - Bibliogr. : p. 774-775 (51 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): PYRIMIDINES -- CARBAZOLE -- DYE-SENSITIZED SOLAR CELLS Аннотация: Novel donor-pi-acceptor dyes bearing the pyrimidine unit as an electron-withdrawing group have been synthesized by using combination of two processes, based on the microwave-assisted Suzuki cross-coupling reaction and nucleophilic aromatic substitution of hydrogen. Spectral properties of the obtained dyes in six aprotic solvents of various polarities have been studied by ultraviolet-visible and fluorescence spectroscopy. In contrast to the absorption spectra, fluorescence emission spectra displayed a strong dependence from their solvent polarities. The nature of the observed long wavelength maxima has been elucidated by means of quantum chemical calculations. The electrochemical properties of these dyes have been investigated by using cyclic voltammetry, while their photovoltaic performance was evaluated by a device fabrication study. The experimental and calculation data show that all of the dyes can be regarded as potentially good photosensitizers for dye-sensitized solar cells. \\\\expert2\\nbo\\Journal of Fluorescence\\2015, v.25, p.763-775.pdf |
D 47 Detection of nitroaromatic explosives by new D-π-A sensing fluorophores on the basis of the pyrimidine scaffold [Electronic resource] / E. V. Verbitskiy, A. A. Baranova, K. I. Ludovik, M. Z. Shafikov, K. O. Khokhlov, E. M. Cheprakova, G. L. Rusinov, O. N. Chupakhin, V. N. Charushin // Analytical and Bioanalytical Chemistry. - 2016. - Ahead of Print Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): NITROAROMATIC EXPLOSIVES -- PYRIMIDINE SCAFFOLD Аннотация: A series of D-π-A- type dyes based on pyrimidines, bearing various thiophene linkers, have been studied as sensing fluorophores. Fluorescence studies have demonstrated that the emission of all derivs. is sensitive to the presence of nitroarom. explosives, such as 2,4,6-trinitrophenol (PA), 2,4,6-trinitrotoluene (TNT), and 2,4-dinitrotoluene (DNT), in their acetonitrile solns. The detection limits of fluorophores to PA, TNT, and DNT proved to be in the range from 5.83 × 10-6 to 2.38 × 10-7 mol/L, 1.70 × 10-4 to 8.40 × 10-6 mol/L, and 8.39 × 10-5 to 6.87 × 10-6 mol/L, resp. The theor. investigation into the quenching mechanism in the presence of fluorophore has been performed. All compds. have shown a good efficiency as sensor materials when tested as elements of the original device < \\\\expert2\\nbo\\Analytical and Bioanalytical Chemistry\\2016, Ahead Print.pdf |
F 70 Fluorescent Detection of 2,4-DNT and 2,4,6-TNT in Aqueous Media by Using Simple Water-Soluble Pyrene Derivatives [Electronic resource] / I. S. Kovalev, O. S. Taniya, N. V. Slovesnova, G. A. Kim, S. Santra, G. V. Zyryanov, D. S. Kopchuk, A. Majee, V. N. Charushin, O. N. Chupakhin // Chemistry - An Asian Journal. - 2016. - Vol. 11, № 5. - С. 775-781. - Bibliogr. : p. 780-781 (39 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): HERBICIDES -- PYRENE DERIVATIVES -- 2,4-DNT -- 2,4,6-TNT Аннотация: Pyrene-contg. water-sol. probes for the fluorescent detection of nitroarom. compds. (NACs), such as explosive components (2,4-DNT and 2,4,6-TNT) and herbicides (2,4-dinitrocresol, 2,4-DNOC), in aq. media are reported. In the probes, the introduction of surface-active hydrophilic heads at the periphery of lipophilic (i.e., hydrophobic) pyrene tails resulted in the formation of highly fluorescent micelle-like aggregates/pre-assocs. in aq. solns. at concns. of ≤10-5M. The enhanced fluorescence quenching of the herein reported architectures is achieved in the presence of ultra-trace amts. of TNT or 2,4-DNT with values of Stern-Volmer quenching const. close to 1 × 105M and a detection limit as low as 182 ppb. The most hydrophilic probes demonstrated higher response to 2,4-DNT over TNT. Filter paper test strips impregnated with 1 × 10-5M solns. of the probes were able to detect TNT, 2,4-DNT, and other NACs at levels as low as 50 ppb in water. \\\\expert2\\NBO\\Chemistry - an Asian Journal\\2016. 11(5). P. 775-781.pdf |
N 52 New 2H-[1,2,3]triazolo[4,5-e][1,2,4]triazolo[1,5-a]pyrimidine derivatives as luminescent fluorophores for detection of nitroaromatic explosives [Electronic resource] / E. V. Verbitskiy, E. B. Gorbunov, A. A. Baranova, K. I. Ludovik, K. O. Khokhlov, E. M. Cheprakova, G. A. Kim, G. L. Rusinov, O. N. Chupakhin, V. N. Charushin // Tetrahedron. - 2016. - Vol. 72, № 32. - С. 4954-4961 Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): CARBAZOLE -- NITROAROMATIC EXPLOSIVES -- TRIPHENYLAMINE Аннотация: A number of D-pi-A type dyes on the basis of new 2H[1,2,3]triazolo[4,5-e][1,2,4]triazolo[1,5-a]pyrimidines, bearing various electron-donating carbazole and triphenylamine fragments, have been studied as sensing fluorophores. Fluorescence studies have demonstrated that emission spectra of these compounds in acetonitrile are sensitive to the presence of nitroaromatic explosives, such as 2,4-dinitroanisole (DNAN), picric acid (PA), styphnic acid (SA), 1,3,5-triethoxy-2,4,6-trinitrobenzene (TETNB), 2,4-dinitrotoluene (DNT), 2,4,6-trinitrotoluene (TNT) and nitrobenzene (NB). Detection limits of fluorophores for DNAN, PA, SA, TETNB, DNT and TNT proved to be in the range from 4.82x10(-1) to 2.96x10(-3) mol/L, 2.10x10(-3) to 5.98x10(-5) mol/L, 1.26x10(-1) to 2.02x10(-4) mol/L, 1.58 x 10(-1) to 1.62x10(-3) mol/L, 1.26x10(-1) to 5.61x10(-4) mol/L and 9.01x10(-2) to 2.77x10(-3) mol/L, respectively. Selective fluorescence quenching response, including a sharp color change under UV irradiation (especially for PA, SA and DNT), makes these compounds promising fluorescence chemosensors for nitroaromatic explosives \\\\expert2\\NBO\\Tetrahedron\\2016, v. 72 , p. 4954-4961.pdf |
S 98 Synthesis and Photophysical Studies of 2-(Thiophen-2-yl)-4-(morpholin-4-yl) quinazoline Derivatives [Electronic resource] / E. V. Nosova, T. N. Moshkina, G. N. Lipunova, D. S. Kopchuk, P. A. Slepukhin, I. V. Baklanova , V. N. Charushin // European Journal of Organic Chemistry. - 2016. - № 16. - С. 2876-2881 Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): PHOTOPHYSICS -- CHARGE TRANSFE -- FLUORESCENCE Аннотация: The synthesis of a series of push-pull aryl and arylethynyl 2-(thiophen-2-yl) quinazoline derivatives is presented. The photophysical properties of the newly generated compounds are also described. Functionalization of the (2-thienyl) quinazoline fluorophore at the 5'-position with aryl and arylethynyl moieties was performed using bromination and subsequent palladium-catalyzed cross-coupling reactions. Optical studies revealed that 4-(diethylamino) phenyl and 4-(diphen-ylamino) phenyl derivatives emit green light upon irradiation, whereas their 4-(9H-carbazol-9-yl) phenyl, methoxyphenyl, thienyl and arylethynyl counterparts are characterized by blue light emission capabilities. The effect of protonation has also been studied, and the ability of some of these molecules to function as colorimetric and luminescent pH sensors has been demonstrated with significant color changes and luminescence switching upon the introduction of acid. \\\\expert2\\NBO\\European Journal of Organic Chemistry\\2016, №16. p.2876-2881.pdf |
N 52 New 4,5-di(hetero)arylpyrimidines as sensing elements for detection of nitroaromatic explosives in vapor phase / E. V. Verbitskiy, A. A. Baranova, K. I. Lugovik, K. O. Khokhlov, E. M. Cheprakova, M. Z. Shafikov, G. L. Rusinov, O. N. Chupakhin, V. N. Charushin // Dyes and Pigments. - 2016. - Vol. 137. - С. 360-371. - Bibliogr. : p. 370-371 (50 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): 4,5-DI(HETERO)ARYLPYRIMIDINES -- NITROAROMATIC EXPLOSIVES -- VAPOR PHASE Аннотация: A series of D–π–A–π–D type dyes based on pyrimidines, bearing thiophene linkers, have been studied as sensing fluorophores. Fluorescence studies have demonstrated that the emission of all derivatives is sensitive to the presence of 2,4,6-trinitrotoluene (TNT) and other nitroaromatic compounds (NACs), in their acetonitrile solutions. The detection limits of fluorophores to NACs proved to be in the range from 10−4 to 10−6 mol/L. The time-resolved fluorescence measurements and theoretical investigation into the quenching mechanism in the presence of fluorophore has been performed. The two types of sensor prototypes for handheld sniffer «Nitroscan» (Plant «Promautomatika», Ekaterinburg, Russia) on the basis of non-woven dry wipe and spunlace non-woven fabric with various quantities of the most sensitive fluorophore have been fabricated. The reusable, reversible and sensitive response of the designed prototypes to NACs enables one to qualify these compounds as promising fluorescent sensory materials for detection of NACs. \\\\expert2\\nbo\\Dyes and Pigments\\2016, v. 137, p.360-371.pdf |
M 65 Microwave-assisted synthesis of 4-(2,2'-bithiophen-5-yl)-5-phenylpyrimidine derivatives as sensors for detection of nitroaromatic explosives = Микроволновый синтез производных 4-(2,2'-битиофенил-5-ил)-5-фенилпиримидина и их применение в качестве сенсоров нитроароматических взрывчатых веществ / E. V. Verbitskiy, E. M. Cheprakova, A. A. Baranova, K. O. Khokhlov, K. I. Ludovik, G. L. Rusinov, O. N. Chupakhin, V. N. Charushin // Chemistry of Heterocyclic Compounds. - 2016. - Vol. 52, № 11. - С. 904-909. - Bibliogr. : p. 909 (27 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): PYRIMIDINE TRIPHENYLAMINE -- NITROAROMATIC EXPLOSIVES -- FLUORESCENCE QUENCHING Аннотация: A reaction sequence involving microwave-assisted Suzuki cross-coupling steps and bromination with N-bromosuccinimide was used to synthesize 4-{4-[4',5'-bis(4-diphenylaminophenyl)-3'-hexyl-2,2'-bithiophen-5-yl]pyrimidin-5-yl}benzonitrile. The optical properties of the obtained compound were studied to evaluate it for possible applications as a sensor of nitroaromatic compounds in acetonitrile solutions and gas phase \\\\expert2\\NBO\\Chemistry of Heterocyclic Compounds\\2016, v.52, N 11, p. 904-909.pdf |
S 98 Synthesis and properties of new π-conjugated imidazole/carbazole structures / R. A. Irgashev, N. A. Kazin, N. I. Makarova, I. V. Dorogan, V. V. Malov, A. R. Tameev, G. L. Rusinov, A. V. Metelitsa, V. I. Minkin, V. N. Charushin // Dyes and Pigments. - 2017. - Vol. 141. - P512-520 Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): IMIDAZOLES -- CARBAZOLES -- ABSORPTION SPECTRA -- PHOTOLUMINESCENCE -- TDDFT CALCULATIONS -- CHARGE MOBILITY Аннотация: New 3-(1H-imidazol-2-yl)-9H-carbazoles and 6,6′-di(1H-imidazol-2-yl)-9H,9′H-3,3′-bicarbazoles have been prepared, starting from 9-ethyl-9H-carbazole-3-carbaldehyde or 9,9′-diethyl-9H,9′H-[3,3′-bicarbazole]-6,6′-dicarbaldehyde through their reactions with 4-methoxyaniline or 4-fluoroaniline, benzil or 2,2′-thenil [1,2-di(thien-2,2′-yl) glyoxal] and ammonium acetate on reflux in glacial acetic acid. The obtained compounds have been shown to demonstrate an effective fluorescence in the blue spectral region, exhibiting quantum yields in the range of 0.08–0.51, depending on their molecular structure and solvent polarity. The nature of the observed absorption spectra has been elucidated by the TDDFT calculations. |
N 52 New 4,5-di(hetero)arylpyrimidines as sensing elements for detection of nitroaromatic explosives in vapor phase / E. V. Verbitskiy, A. A. Baranova, K. I. Lugovik, K. O. Khokhlov, E. M. Cheprakova, M. Z. Shafikov, G. L. Rusinov, O. N. Chupakhin, V. N. Charushin // Dyes and Pigments. - 2017. - Vol. 137. - P360-371 Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): FLUORESCENCE QUENCHING -- NITROAROMATIC EXPLOSIVES -- TRIPHENYLAMINES -- CARBAZOLES -- PYRIMIDINES Аннотация: A series of D–π–A–π–D type dyes based on pyrimidines, bearing thiophene linkers, have been studied as sensing fluorophores. Fluorescence studies have demonstrated that the emission of all derivatives is sensitive to the presence of 2,4,6-trinitrotoluene (TNT) and other nitroaromatic compounds (NACs), in their acetonitrile solutions. The detection limits of fluorophores to NACs proved to be in the range from 10−4 to 10−6 mol/L. The time-resolved fluorescence measurements and theoretical investigation into the quenching mechanism in the presence of fluorophore has been performed. The two types of sensor prototypes for handheld sniffer «Nitroscan» (Plant «Promautomatika», Ekaterinburg, Russia) on the basis of non-woven dry wipe and spunlace non-woven fabric with various quantities of the most sensitive fluorophore have been fabricated. The reusable, reversible and sensitive response of the designed prototypes to NACs enables one to qualify these compounds as promising fluorescent sensory materials for detection of NACs. |
E 97 Extended cavity pyrene-based iptycenes for the turn-off fluorescence detection of RDX and common nitroaromatic explosives / A. F. Khasanov [et al.] // New Journal of Chemistry. - 2017. - Vol. 41, № 6. - P2309-2320 Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): PYRENE (CHEMICAL) -- FLUORESCENCE -- RDX (CYCLONITE) Аннотация: Extended cavity pyrene-based iptycenes have been synthesized by using the Diels–Alder reaction between in situ generated dehydropyrenes and anthracene. The photophysical properties and the interaction of these iptycenes with nitro-explosive components were studied both in solution and in the solid state by using fluorescence spectroscopy and X-ray crystallography, respectively. Due to the presence of both the large iptycene cavity and the central pyrene core, an unprecedently high fluorescence-quenching response towards non-aromatic and non-planar 1,3,5-trinitroperhydro-1,3,5-triazine (RDX) has been observed both in solution (with an apparent Stern–Volmer constant value aKSV up to 1.53 × 103 M−1) and in the vapor phase (50–75% fluorescence quenching of the PU films doped with chemosensors). In the case of nitroaromatic explosives, nitrobenzene (NB), 2,4-DNT, TNT, and 2,4,6-trinitrophenol (TNP or picric acid, PA), pyrene-based iptycenes also demonstrate a good fluorescence-quenching response both in solutions (with apparent Stern–Volmer constant values aKSV = 0.4–8.0 × 103 M−1) and in the vapor phase (up to 90% fluorescence quenching of the PU films doped with chemosensors). The “sphere of action” fluorescence quenching model was suggested. \\\\Expert2\\NBO\\New Journal of Chemistry\\2017 v.41 p.2309-2320.pdf |
Synthesis and characterization of linear 1,4-diazine-triphenylamine–based selective chemosensors for recognition of nitroaromatic compounds and aliphatic amines / E. V. Verbitskiy, Y. A. Kvashnin, E. F. Zhilina [et al.] // Dyes and pigments. - 2020. - Vol. 178. - P108344 Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): ALIPHATIC AMINES -- FLUORESCENCE QUENCHING -- NITROAROMATIC COMPOUNDS -- PYRAZINE -- QUINOXALINE -- SOLVATOCHROMISM Аннотация: Novel 1,4-diazine-based dyes of the D–π–A type, possessing triphenylamine as an electron-donating group, have been developed. Fluorescence studies have demonstrated that emission of these fluorophores is sensitive towards different nitroaromatic compounds and aliphatic amines, both in solutions and in a vapor phase. Moreover, these compounds can be considered as “naked-eye” fluorescent probes for solution polarity because they possess pronounced solvatochromic properties. Therefore, these compounds have to be regarded as potential multifunctional chemosensors for monitoring hazardous organic substances. |
Design of fluorescent sensors based on azaheterocyclic push-pull systems towards nitroaromatic explosives and related compounds: a review / E. V. Verbitskiy, G. L. Rusinov, O. N. Chupakhin, V. N. Charushin // Dyes and pigments. - 2020. - Vol. 180. - P108414 Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): NITROAROMATIC EXPLOSIVES -- FLUORESCENCE QUENCHING -- PYRIDINES -- PYRAZINE -- PYRIMIDINES -- TRIAZINES Аннотация: Highly sensitive and selective detection of nitro containing high energy organic compounds such as picric acid (PA), 2,4,6-trinitrotoluene (TNT) and 2,4-dinitrotoluene (DNT) has become a challenging task due to concerns over national security, criminal investigations and environment protections. Among various known detection methods, fluorescence sensors have gained special attention in recent time. The family of fluorescent sensors based on push-pull systems that incorporate nitrogen heterocycles as an electron-withdrawing group have a growing interest due to their high sensitivity, selectivity and easy tuning. The fluorescent sensors discussed in this review are classified and organized according to used azaheterocyclic scaffold, their functionality and their ability to detect of nitroaromatics by fluorescence quenching. |
Synthesis and photophysical studies of novel v-shaped 2,3-bis{5-aryl-2-thienyl}(dibenzo[f,h])quinoxalines / T. N. Moshkina, E. V. Nosova, A. E. Kopotilova [et al.] // Asian journal of organic chemistry. - 2020. - Vol. 9, № 4. - P673-681 Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): CROSS-COUPLING -- DIBENZO[F,H]QUINOXALINE -- DONOR-ACCEPTOR-DONOR CHROMOPHORES -- FLUORESCENCE -- SENSORS Аннотация: A series of novel V-shaped luminophores containing electron-withdrawing dibenzo[f,h]quinoxaline core and arylthienyl donor fragments at positions 2 and 3 has been synthesized. The absorption spectra (UV/vis) were recorded in several solvents, whereas emission spectra were recorded in solutions and powders. The solvatochromism as well as halochromism of obtained compounds was also explored. Electronic-structure calculations using quantum-chemistry methods were performed to further analyse experimental results. All characteristics were compared with that of 2,3-bis(arylthienyl)quinoxaline counterparts. The halochromic effect studies showed that upon gradual addition of trifluoroacetic acid (TFA) to the toluene solution of diethylaminophenyl-substituted dibenzo[f,h]quinoxaline chromophore, absorption and emission changed. Observed band shifts were more distinct in the case of mentioned quinoxaline than for other derivatives. All of the (dibenzo[f,h])quinoxaline chromophores exhibited good sensitivity toward nitro-containing explosives with high Stern-Volmer constants up to 57800 M−1, these results are remarkable for such heterocyclic systems. |
Synthesys and photophysical properties of 2-(het)arylderivatives of 4-morpholinylquinazolines / E. V. Nosova, T. N. Moshkina, Ju. V. Permyakova [et al.] // Actual problems of organic chemistry and biotechnology. - Екатеринбург, 2020. - P281-283 Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): 4-(4-MORPHOLINYL)QUINAZOLINES -- CROSS-COUPLING -- FLUORESCENCE |
Azaheterocyclic push-pull chromophores: synthesis, photophysical properties and applications as fluorescent sensors / E. V. Verbitskiy, G. L. Rusinov, O. N. Chupakhin, V. N. Charushin // Actual problems of organic chemistry and biotechnology. - Екатеринбург, 2020. - P73-75 Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): PYRIMIDINE -- PYRAZINE -- FLUORESCENCE QUENCHING -- PUSH-PULL FLUOROPHORES |
Asymmetrically substituted 5,5′′-diaryl-2,2′:6′,2′′-terpyridines as efficient fluorescence “turn-on” probes for Zn2+ in food/cosmetic samples and human urine / O. V. Shabunina, E. S. Starnovskaya, Y. K. Shaitz [et al.] // Journal of photochemistry and photobiology A: Chemistry. - 2021. - Vol. 408. - P113101 Рубрики: ХИМИЧЕСКИЕ НАУКИ |
A 10 A new approach to 4-arylstyrenes: microwave-assisted synthesis and photophysical properties / M. Z. Eddin, M. G. Pervova, E. F. Zhilina [et al.] // Russian chemical bulletin. - 2021. - Vol. 70, № 11. - P2139-2144 Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): STYRENE -- 4-VINYLBIPHENYL DERIVATIVES -- SUZUKi—MIYAURA CROSS-COUPLING -- FLUORESCENCE |
T 44 The Rh(III)-catalysed C-H/N-H annulation of 2-thienyl- and 2-phenyl-quinazolin-4(3: H)-ones with diphenylacetylene / T. N. Moshkina, E. V. Nosova, G. N. Lipunova [et al.] // New Journal of Chemistry. - 2021. - Vol. 45, № 19. - P8456-8466 Рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: A series of 4,5-diphenyl-7H-thieno[2′,3′:3,4]pyrido[2,1-b]quinazolin-7-ones was synthesized via the Rh(III)-catalyzed annulation of 2-thienylquinazolin-4(3H)-ones with diphenylacetylene. 2-Phenylquinazolin-4(3H)-one amide alcoholysis and double C–H functionalization proceeded under the same reaction conditions with the formation of 2,3,7,8-tetraphenyl-1H-benzo[d,e][1,8]-naphthyridine derivatives. All compounds possess fluorescence properties in MeCN and toluene solutions as well as in the solid state. The aggregation induced emission (AIE) properties and the ability to detect Fe3+ cations were evaluated. |
Substituted 2-(2-hydroxyphenyl)–3H-quinazolin-4-ones and their difluoroboron complexes: Synthesis and photophysical properties / T. N. Moshkina, E. V. Nosova, V. N. Charushin [et al.] // Spectrochimica acta part A: molecular and biomolecular spectroscopy. - 2021. - Vol. 252. - P119497 Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): ESIPT -- FLUORESCENCE -- O-LIGAND -- BF2-COMPLEX2-(2-HYDROXYPHENYL)–3H-QUINAZOLIN-4-ONES Аннотация: 2-(2-Hydroxyphenyl)–3H-quinazolin-4-ones with diverse substituents at phenol ring and their six-membered difluoroboron complexes have been synthesized via few-stage approach. The photophysical properties of target compounds have been investigated in two solvents as well as in the solid state. The nature of substituents and substitution point in the phenol moiety of ligands and resulting BF2-complexes on the photophysical properties of dyes have been explored. The complex bearing two t-Bu groups proved to be the most emissive in solid state, whereas its 5-methoxy and 4-diethylamino counterparts possess strong emission in toluene solution. The dyes exhibited large Stokes shifts which was attributed to excited state intramolecular proton transfer (ESIPT). Additionally, fluorescence of quinazolinones in the mixture of THF/water was studied. All ligands demonstrated emission enhancement with increase of water fraction which was due to aggregation induced emission. |
Computer vision vs. spectrofluorometer-assisted detection of common nitro-explosive components with bola-type PAH-based chemosensors / I. S. Kovalev, L. K. Sadieva, O. S. Taniya [et al.] // RSC Advances. - 2021. - Vol. 11, № 42. - P25850-25857 Рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: Computer vision (CV) algorithms are widely utilized in imaging processing for medical and personal electronics applications. In sensorics CV can provide a great potential to quantitate chemosensors' signals. Here we wish to describe a method for the CV-assisted spectrofluorometer-free detection of common nitro-explosive components, e.g. 2,4-dinitrotoluene (DNT) and 2,4,6-trinitrotoluene (TNT), by using polyaromatic hydrocarbon (PAH, PAH = 1-pyrenyl or 9-anthracenyl) – based bola-type chemosensors. The PAH components of these chemical bolas are able to form stable, bright emissive in a visual wavelength region excimers, which allows their use as extended matrices of the RGB colors after imaging and digital processing. In non-polar solvents, the excimers have poor chemosensing properties, while in aqueous solutions, due to the possible micellar formation, these excimers provide “turn-off” fluorescence detection of DNT and TNT in the sub-nanomolar concentrations. A combination of these PAH-based fluorescent chemosensors with the proposed CV-assisted algorithm offers a fast and convenient approach for on-site, real-time, multi-thread analyte detection without the use of fluorometers. Although we focus on the analysis of nitro-explosives, the presented method is a conceptual work describing a general use of CV for quantitative fluorescence detection of various analytes as a simpler alternative to spectrofluorometer-assisted methods. |