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1.
Isotopic splitting patterns in the 13C NMR spectra of some partially deuterated 1‐aryl‐2‐(phenyldiazenyl)butane‐1,3‐dione and 4‐hydroxy‐3‐(phenyldiazenyl)‐2H‐chromen‐2‐one: evidence for elucidation of tautomeric forms 下载免费PDF全文
Nuclear magnetic resonance spectra of synthesized azo dyes derived from aniline derivatives in reaction with benzoylacetone and 4‐hydroxycoumarin were studied in both CDCl3 and (CD3)2SO (two drops of D2O were added into solutions of dyes). All dyes showed intramolecular hydrogen bonding. Dyes derived from o‐nitro aniline in the reaction with benzoylacetone, and 4‐hydroxycoumarin showed bifurcated intramolecular hydrogen bonds. The solvent‐substrate proton exchange of dyes derived from benzoylacetone and 4‐hydroxycoumarin was examined in the presence of two drops of D2O. Among ten dye samples, two dyes derived from benzoylacetone did not show deuteration, three dyes showed partial deuteration and five dyes showed full deuteration under similar conditions. For the partially deuterated dyes the β‐isotope effect in 13C splitting was investigated and was used for the determination of the predominant tautomeric form. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
2.
The preparation of 2-phenyl-5H-phenaleno[ 1,9-bc]pyran-5-one ( 7 ) is described. Compound 7 undergoes reactions typical of pyrones and was therefore a useful intermediate for the preparation of pyrylium salts. Several pyrylium dyes were prepared from 7 and the long-wavelength absorptions of these dyes were compared with those of the corresponding flavylium dyes. 相似文献
3.
Dr. Kamal Prakash Ajyal Z. Alsaleh Neeraj Pinki Rathi Ankit Sharma Prof. Dr. Muniappan Sankar Prof. Dr. Francis D'Souza 《Chemphyschem》2019,20(20):2627-2634
Three new ‘push-pull’ A3B Zn(II)porphyrin dyes having meso-pyrenyl, carbazolyl and phenothiazine as electron donors ( A ) and phenylcarboxylic acid as acceptor/anchor ( B ) were synthesized and utilized for DSSC application. The spectral and electrochemical redox properties of these new dyes were studied and compared with trans-A2BC Zn(II) porphyrin dyes under similar experimental conditions. Red-shifted, broadened absorption peaks, lower fluorescence quantum yields, and shortened lifetimes were observed for the A3B dyes as compared to zinc tetraphenylporphyrin control, ZnTPP. DFT optimized structures suggested effective charge separation related to enhanced charge injection efficiency. Driving force for electron injection (ΔGinj) and dye regeneration (ΔGreg) calculated from the spectral and electrochemical studies predicted facile electron injection from excited dye into semiconductor TiO2 in the constructed solar cells. Phenothiazine appended dye ( KP - TriPTZ - Zn ) showed the highest η value of 7.3 % for PCE with greater Jsc and Voc values due to its better light harvesting ability and reduced dye aggregation as compared to other dyes. Our studies demonstrate that the dyes having multiple electron-donating groups exhibit higher photon-to-current conversion efficiency. 相似文献
4.
L. Schneider 《Helvetica chimica acta》1968,51(1):67-74
Disazo dyes from 6-amino-1-hydroxy-naphthalene-3-sulfonic acid (J acid) were synthesized by coupling ortho-hydroxy monoazo dyes with different diazonium compounds in acid medium (dyes No 3 – 14 . A second coupling to the ortho position of the amino group was also possible with the copper complexes of o,o' -dihydroxy monoazo dyes from 8-amino-1-hydroxynaphthalene-3,6-disulfonic acid (H acid) dyes No 19 – 22 ). This is a reversal of the well known rule that the formation of disazo dyes with aminonaphthol-sulfonic acids is only practicable when an acid coupling is followed by an alkaline one. 5-Amino-1-hydroxy-naphthalene-3-sulfonic acid (M acid), which is said to form no disazo dyes, could be coupled twice with several diazonium compounds to yield disazo dyes (dyes No 24 , 26 , 27 , 29 ). 相似文献
5.
Nurcan Kurtoglu Mehmet Aslantaş Huseyin Zengin Ertan Şahin Mukerrem Kurtoglu 《Chemical Papers》2010,64(5):645-651
This study focuses on the preparation, single crystal X-ray diffraction, characterization, and optical properties of some
anthraquinone-based dyes. The anthraquinone-based antimicrobial dye N-{2-[(9,10-dioxo-9,10-dihydroanthracen-1-yl)amino]-2-oxoethyl}-N,N-dimethylbutan-1-aminium chloride monohydrate (III) was obtained from 1-aminoanthraquinone (I) via 2-chloro-N-(9,10-dioxo-9,10-dihydroanthracen-1-yl)acetamide (II) using known preparation and characterization methods. Single crystal X-ray diffraction analysis of III revealed a monoclinic system, space group P21/n, Z = 4. Photoluminescence properties of anthraquinone dyes I–III were also investigated. These dyes gave an intense emission (λmax = 341 nm) upon the irradiation by UV light and showed photoluminescence quantum yields of 73 %, 66 %, and 61 % with long
excited-state lifetimes of 6.87 ns, 6.14 ns, and 5.69 ns, respectively. These anthraquinone dyes are of interest as an organic
light emitting material for electroluminescent devices. 相似文献
6.
Dr. Ming Cheng Prof. Xichuan Yang Dr. Jiajia Li Dr. Cheng Chen Dr. Jianghua Zhao Yu Wang Prof. Licheng Sun 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(50):16196-16202
New hemicyanine dyes ( CM101 , CM102 , CM103 , and CM104 ) in which tetrahydroquinoline derivatives are used as electron donors and N‐(carboxymethyl)‐pyridinium is used as an electron acceptor and anchoring group were designed and synthesized for dye‐sensitized solar cells (DSSCs). Compared with corresponding dyes that have cyanoacetic acid as the acceptor, N‐(carboxymethyl)‐pyridinium has a stronger electron‐withdrawing ability, which causes the absorption maximum of dyes to be redshifted. The photovoltaic performance of the DSSCs based on dyes CM101 – CM104 markedly depends on the molecular structures of the dyes in terms of the n‐hexyl chains and methoxyl. The device sensitized by dye CM104 achieved the best conversion efficiency of 7.0 % (Jsc=13.4 mA cm?2, Voc=704 mV, FF=74.8 %) under AM 1.5 irradiation (100 mW cm?2). In contrast, the device sensitized by reference dye CMR104 with the same donor but the cyanoacetic acid as the acceptor gave an efficiency of 3.4 % (Jsc=6.2 mA cm?2, Voc=730 mV, FF=74.8 %). Under the same conditions, the cell fabricated with N719 sensitized porous TiO2 exhibited an efficiency of 7.9 % (Jsc=15.4 mA cm?2, Voc=723 mV, FF=72.3 %). The dyes CM101 – CM104 show a broader spectral response compared with the reference dyes CMR101 – CMR104 and have high IPCE exceeding 90 % from 450 to 580 nm. Considering the reflection of sunlight, the photoelectric conversion efficiency could be almost 100 % during this region. 相似文献
7.
Bi‐anchoring Organic Dyes that Contain Benzimidazole Branches for Dye‐Sensitized Solar Cells: Effects of π Spacer and Peripheral Donor Groups 下载免费PDF全文
Govardhana Babu Bodedla Dr. K. R. Justin Thomas Miao‐Syuan Fan Prof. Kuo‐Chuan Ho 《化学:亚洲杂志》2016,11(18):2564-2577
Benzimidazole‐branched bi‐anchoring organic dyes that contained triphenylamine/phenothiazine donors, 2‐cyanoacrylic acid acceptors, and various π linkers were synthesized and examined as sensitizers for dye‐sensitized solar cells. The structure–activity relationships in these dyes were systematically investigated by using absorption spectroscopy, cyclic voltammetry, and density functional theory calculations. The wavelength of the absorption peak was more‐heavily influenced by the nature of the π linker than by the nature of the donor. For a given donor, the absorption maximum (λmax) was red‐shifted on changing the π linker from phenyl to 2,2′‐bithiophene, whilst the dyes that contained triphenylamine units displayed higher molar extinction coefficients (?) than their analogous phenothiazine‐based triphenylamine dyes, which led to good light‐harvesting properties in the triphenylamine‐based dyes. Electrochemical data for the dyes indicated that the triphenylamine‐based dyes possessed relatively low‐lying HOMOs, which could be beneficial for suppressing back electron transfer from the conduction band of TiO2 to the oxidized dyes, owing to facile regeneration of the oxidized dye by the electrolyte. The best performance in the DSSCs was observed for a dye that possessed a triphenylamine donor and 2,2′‐bithiophene π linkers. Electron impedance spectroscopy (EIS) studies revealed that the use of triphenylamine as the donor and phenyl or 2,2′‐bithiophene as the π linkers was beneficial for disrupting the dark current and charge‐recombination kinetics, which led to a long electron lifetime of the injected electrons in the conduction band of TiO2. 相似文献
8.
Synthesis of 1‐(p‐Sulphophenyl)‐3‐methyl‐5‐pyrazolone Based Acid Dyes and Their Applications on Leather 下载免费PDF全文
Ghulam Hussain Nasir Abbas Makshoof Ather Misbah Ul Ain Khan Aamer Saeed Rashid Saleem Ghulam Shabir 《中国化学会会志》2016,63(8):645-652
A new series of pyrazolone based azo acid dyes (3a–g) has been synthesized starting from 1‐(p‐sul‐phophenyl)‐3‐methyl‐5‐pyrazolone (1). The synthetic methodology included the nitrosation of p‐sulphophenyl methyl pyrazolone followed by reduction, diazotization and coupling with Naphthol AS derivatives (2a–f), in alkaline medium to yield different acid dyes. Multichromic metal complexes of these dyes (5a–f, 6a–f and 7a–f) with 3d transition metals Chromium, Iron and Copper were also synthesized. The structures of all of newly synthesized compounds were confirmed by analytical data and spectroscopic techniques. The synthesized dyes were applied on leather to assess their light fastness, wash fastness and rubbing fastness and were shown to exhibit high values of 4–5 for majority of dyes. 相似文献
9.
4‐Phenyl‐2‐aminothaizole was diazotized and coupled with N‐(alkyl)‐2‐oxo‐3‐cyano‐4‐methyl‐6‐hydroxypyridine (2‐pyridone). The resultant dyes were named as N‐(alkyl)‐6‐hydroxy‐4‐methyl‐2‐oxo‐5‐((4‐phenylthiazole‐2‐yl)diazenyl)‐1,2‐dihydro pyridine‐3‐carbonitrite and duly characterized. The diazotized aryl amines were then coupled to a moiety of above‐mentioned dyes at 5‐position of thiazole. The obtained bisheteroaryl azo dyes were characterized by elemental analysis and spectral studies. Solvent effects on the visible absorption spectra of the dyes were evaluated. The color of the dyes is discussed with respect to the nature of the heterocyclic ring, aromatic amines, and substituents present therein. All these dyes were applied as disperse dyes on to polyester fabrics, and their fastness properties were evaluated. © 2013 Wiley Periodicals, Inc. Heteroatom Chem 24:208–220, 2013; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.21085 相似文献
10.
Dr. Sahng Ha Lee Da Som Choi Dr. Milja Pesic Yang Woo Lee Dr. Caroline E. Paul Prof. Dr. Frank Hollmann Prof. Dr. Chan Beum Park 《Angewandte Chemie (International ed. in English)》2017,56(30):8681-8685
Enoate reductases from the family of old yellow enzymes (OYEs) can catalyze stereoselective trans-hydrogenation of activated C=C bonds. Their application is limited by the necessity for a continuous supply of redox equivalents such as nicotinamide cofactors [NAD(P)H]. Visible light-driven activation of OYEs through NAD(P)H-free, direct transfer of photoexcited electrons from xanthene dyes to the prosthetic flavin moiety is reported. Spectroscopic and electrochemical analyses verified spontaneous association of rose bengal and its derivatives with OYEs. Illumination of a white light-emitting-diode triggered photoreduction of OYEs by xanthene dyes, which facilitated the enantioselective reduction of C=C bonds in the absence of NADH. The photoenzymatic conversion of 2-methylcyclohexenone resulted in enantiopure (ee>99 %) (R)-2-methylcyclohexanone with conversion yields as high as 80–90 %. The turnover frequency was significantly affected by the substitution of halogen atoms in xanthene dyes. 相似文献
11.
A series of novel monoazo disperse dyes based on 2-amino-5-nitro-4-(p-nitrophenyl)thiazole were prepared using various N,N-dialkylaniline derivatives as the coupling components. The spectral properties in the IR and visible range of the dyes were investigated. The dyeing performance of these dyes was assessed on nylon fabric. These dyes were found to give a wide range of color shades from reddish brown to indigo with excellent brightness, levelness, and depth on nylon fabric. The dyed fabric showed fairly good light fastness, good to excellent fastness to wash and perspiration, and excellent fastness to sublimation. The dyebath exhaustion and fixation of the dyes on nylon were found to be very good and acceptable. 相似文献
12.
M. Asha Jhonsi A. Kathiravan G. Paramaguru C. Manivannan R. Renganathan 《Journal of solution chemistry》2010,39(10):1520-1530
Fluorescence quenching of [Ru(bpy)3]2+ by a series of organic dyes has been investigated by using the steady state fluorescence technique in aqueous medium. The
dyes used are anthraquinone dyes: uniblue, acid blue 129, alizarin, alizarin red S and the azo dyes: congo red, sunset yellow,
methyl orange, tartrazine, acid orange 63, methyl red and erichrome black T. The quenching of [Ru(bpy)3]2+ was found to obey the Stern-Volmer equation and the corresponding Stern-Volmer plots were linear indicating dynamic quenching.
The quenching rate constants (k
q) were calculated from the fluorescence data. The mechanism of quenching was discussed on the basis of the quenching rate
constants as well as the reduction potential of dyes. The electron transfer mechanism has been proved by the calculation of
Gibbs energy changes (ΔG
et) by applying the Rehm-Weller equation. 相似文献
13.
Color Tuning of the Aggregation‐Induced Emission of Maleimide Dyes by Molecular Design and Morphology Control 下载免费PDF全文
Dr. Hiroaki Imoto Kohei Kizaki Dr. Seiji Watase Dr. Kimihiro Matsukawa Prof. Kensuke Naka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(34):12105-12111
Aggregation‐induced emission (AIE)‐active maleimide dyes, namely, 2‐p‐toluidino‐N‐p‐tolylmaleimide, 3‐phenyl‐2‐toluidino‐N‐p‐tolylmaleimide, 2‐p‐thiocresyl‐3‐p‐toluidino‐N‐p‐tolylmaleimide, and 2,3‐dithiocresyl‐N‐arylmaleimides, were synthesized by facile synthetic procedures. The dyes show intense emission in the solid state, and emission colors were controlled from green (λmax=527 nm) to orange (λmax=609 nm) by varying the substituents at the 2‐ and 3‐positions of the maleimide and the packing structures in the solid state. 2,3‐Disubstituted maleimide dyes effectively underwent redshifts of their emission wavelength. Furthermore, some of the dyes exhibited mechanochromism and polymorphism, and their emission properties were dramatically dependent on the morphology of the solid samples. The mechanisms of the emission behaviors were investigated by X‐ray diffraction. The substituent of the nitrogen atom of the maleimide ring affected the intermolecular interactions and short contacts, which were observed by single crystal X‐ray crystallography, to result in completely different emission properties. 相似文献
14.
A series of new hetarylazo indole dyes were synthesized by azo coupling of 2-phenyl-, 2-methyl-, and 1-methyl-1-phenyl-1H-indole with diazonium salts derived from 5-methylsulfanyl-1H-1,2,4-triazol-3-amine, 1H-1,2,4-triazol-3-amine, 5-methylisoxazol-3-amine, and 5-amino-1,3,4-thiadiazole-2-thiol. The dyes were characterized by the
IR spectra, electronic absorption spectra in the UV and visible regions, and 1H NMR and mass spectra. The effects of solvent nature, acidity of the medium, temperature, and concentration on the electronic
absorption spectra in the visible region and the dependence of the color of the dyes on the nature of heterocyclic fragment
were examined.
Published in Russian in Zhurnal Organicheskoi Khimii, 2007, Vol. 43, No. 7, pp. 1041–1047.
The text was submitted by the authors in English. 相似文献
15.
Corentin Pigot Guillaume Noirbent Sbastien Peralta Sylvain Duval Malek Nechab Didier Gigmes Frdric Dumur 《Helvetica chimica acta》2019,102(12)
An unprecedented nucleophilic addition of piperidine on an electron acceptor, namely, 2‐(3‐oxo‐2,3‐dihydro‐1H‐cyclopenta[b]naphthalen‐1‐ylidene)malononitrile is reported. This unexpected behavior was observed during the synthesis of push‐pull dyes using the classical Knoevenagel reaction. To overcome this drawback, use of diisopropylethylamine (DIPEA) enabled to produce the expected dyes PP1 and PP2 . The optical and electrochemical properties of the different dyes were examined. Theoretical calculations were also carried out to support the experimental results. To evidence the higher electron‐withdrawing ability of this electron acceptor, a comparison was established with two dyes ( PP3 and PP4 ) comprising its shorter analogue. 相似文献
16.
Hyeran Lee Mikhail Y. Berezin Maged Henary Lucjan Strekowski Samuel Achilefu 《Journal of photochemistry and photobiology. A, Chemistry》2008,200(2-3):438-444
Structurally diverse near-infrared (NIR) absorbing polymethine dyes were prepared and their fluorescence lifetimes (FLT) were evaluated in relation to their structural features. Comparative FLT analysis based on the modification of methine chain length and heterocyclic system showed that indolium or benzo[e]indolium heptamethine dyes exhibited longer FLT than the benzo[c,d]indolium trimethine dye. Modification of heterocyclic system alone with an intact chain length showed that indolium-based heptamethine dyes showed approximately 30% longer FLT than the benzo[e]indolium-based dyes. In general, the FLT of polymethine dyes increased from polar to non-polar solvents. In addition, correlation study between the theoretical and the experimental FLT for indocyanine green (ICG) suggests that the lack of structural rigidity for these cyanine dyes is primarily responsible for the loss of the excited state energy via non-radiative pathway. 相似文献
17.
A series of novel monoazo disperse dyes derived from the coupling of diazotized 2-aminobenzo[b]thiophene derivatives with N-arylmaleimides is described. The monoazo disperse dyes applied to nylon fabric and their dyeing performance has been assessed. These dyes have been found to give light yellow to reddish pink color shades with very good depth and levelness on nylon fabric. The dyed fabric shows moderate light fastness and excellent washing, rubbing, perspiration, and sublimation fastness. The percentage dyebath exhaustion on nylon fabric has been found to be good and acceptable. 相似文献
18.
Volker Leen Dr. Wenwu Qin Prof. Dr. Wensheng Yang Jie Cui Chan Xu Xiaoliang Tang Dr. Weisheng Liu Prof. Dr. Koen Robeyns Dr. Luc Van Meervelt Prof. David Beljonne Prof. Dr. Roberto Lazzaroni Prof. Dr. Claire Tonnelé Noël Boens Prof. Wim Dehaen Prof. 《化学:亚洲杂志》2010,5(9):2016-2026
Starting from the conformationally unconstrained compound 3,5‐di‐(2‐bromophenoxy)‐4,4‐difluoro‐8‐(4‐methylphenyl)‐4‐bora‐3a,4a‐diaza‐s‐indacene ( 1 ), two BODIPY dyes ( 2 and 3 ) with increasingly rigid conformations were synthesized in outstanding total yields through palladium catalyzed intramolecular benzofuran formation. Restricted bond rotation of the phenoxy fragments leads to dyes 2 and 3 , which absorb and fluoresce more intensely at longer wavelengths relative to the unconstrained dye 1 . Reduction of the conformational flexibility in 2 and 3 leads to significantly higher fluorescence quantum yields compared to those of 1 . X‐ray diffraction analysis shows the progressively more extended planarity of the chromophore in line with the increasing conformational restriction in the series 1 → 2 → 3 , which explains the larger red shifts of the absorption and emission spectra. These conclusions are confirmed by quantum chemical calculations of the lowest electronic excitations in 1 , 1a , 2 , 2a , 3 and dyes of related chemical structures. The effect of the molecular structure on the visible absorption and fluorescence emission properties of 1 , 1a , 2 , 2a , 3 has been examined as a function of solvent by means of the new, generalized treatment of the solvent effect (J. Phys. Chem. B 2009 , 113, 5951–5960). Solvent polarizability is the primary factor responsible for the small solvent‐dependent shifts of the visible absorption and fluorescence emission bands of these dyes. 相似文献
19.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(30):8807-8811
Enoate reductases from the family of old yellow enzymes (OYEs) can catalyze stereoselective trans ‐hydrogenation of activated C=C bonds. Their application is limited by the necessity for a continuous supply of redox equivalents such as nicotinamide cofactors [NAD(P)H]. Visible light‐driven activation of OYEs through NAD(P)H‐free, direct transfer of photoexcited electrons from xanthene dyes to the prosthetic flavin moiety is reported. Spectroscopic and electrochemical analyses verified spontaneous association of rose bengal and its derivatives with OYEs. Illumination of a white light‐emitting‐diode triggered photoreduction of OYEs by xanthene dyes, which facilitated the enantioselective reduction of C=C bonds in the absence of NADH. The photoenzymatic conversion of 2‐methylcyclohexenone resulted in enantiopure (ee >99 %) (R )‐2‐methylcyclohexanone with conversion yields as high as 80–90 %. The turnover frequency was significantly affected by the substitution of halogen atoms in xanthene dyes. 相似文献
20.
Mohamed F. Abdel-Megeed Mohamed M. Azaam Gamal A. El-Hiti 《Monatshefte für Chemie / Chemical Monthly》2007,138(2):153-156
Summary. Diazotized 3-amino-2-thioxo-2,3-dihydro-1H-quinazolin-4-one was coupled with various hydroxy aromatics to give the corresponding 3-arylazo-2-thioxo-2,3-dihydro-1H-quinazolin-4-ones in reasonable yields. The dyes produced were applied to polyesters as disperse dyes and their fastness
properties were elevated. 相似文献