- 1,3-Bis(phenylamino)squaraine - Photophysical and photochemical properties
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A novel squarylium dye possessing donor-π-acceptor structure that features a fixed imine phenyl ring as an electron donor and 3,4-dihydroxycyclobut-3-ene-1,2-dione moiety as an electron acceptor was synthesized. The structure of the dye was elucidated by means of NMR and IR spectroscopy and elemental analysis. The compound was studied using steady-state absorption and emission spectroscopy, as well as the time-resolved spectroscopy. The measurements were carried out in solvents of different polarity. The dye absorbs in the visible light region about 400 nm and emits light with low fluorescence quantum yield, below 1 × 10-3 M. An increases polarity of solvent results in a blue-shift of absorption band and red-shift of emission band, respectively. The rate constants of radiative and non-radiative deactivation of excited state depend on the viscosity of solvent used. The bimolecular quenching of excited singlet state of squaraine depends on the rate of diffusion process.
- Kabatc, Janina,Kostrzewska, Katarzyna,Jurek, Katarzyna,Dobosz, Robert,Orze?, ?ukasz
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- Pseudo-oxocarbons complexes - Complexation of 2,4-bis(dicyanomethylene)-cyclobutane-1,3-dione dianion with copper. X-ray identification and electrochemical properties of the dianion and copper(I) and (II) complexes
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The compound (Ph4P)2(trans-cdcb)·2H2O (trans-cdcb2- = 2,4-bis(dicyanomethylene)-cyclobutane-1,3-dione dianion) has been synthesized and characterized by X-ray crystallography. Crystal data: triclinic, space group P1, a = 10.829(2) A, b = 11.297(2) A, c = 11.515(2) A, α = 79.61(1)°, β = 68.54(1)°, γ = 63.49(1)°, V = 1172.9(4) A3, Z = 1, R = 0.036, Rw = 0.047. With the dianion as a ligand, two complexes have been obtained and characterized by X-ray crystallography, UV-visible spectroscopy, and electrochemistry. The copper(II) complex [Cu(trans-cdcb)(H2O)4·2H2O]n consists of polymeric chains with copper atoms bonded to two of the nitrile groups of the ligand. Crystal data: monoclinic, space group P21/c, a = 9.6366(6) A, b = 7.1292(3) A, c = 10.7018(6) A, β = 99.603(4)°, V = 724.92(7) A3, Z = 2, R = 0.026, Rw = 0.041. The copper(I) complex[Cu2(trans-cdcb)(CH3CN)4·2CH 3CN]n consists of polymeric chains with copper atoms bonded by all the four nitrile groups of the ligand. Crystal data: monoclinic, space group P21/n, a = 10.654(2) A, b = 8.736(1) A, c = 14.654(3) A, β = 109.01(2)°, V = 1291.3(9) A3, Z = 2, R = 0.037, Rw = 0.041. In CH3CN solution, the copper complexes are dissociated. Moreover, copper(II) is reduced into copper(I) by the dianion. Electrochemistry in the solid state (polymer coated electrode) showed the redox transitions of the different compounds.
- Fabre, Paul-Louis,Pena, Christophe,Galibert, Anne Marie,Soula, Brigitte,Bernardinelli, Gerald,Donnadieu, Bruno,Castan, Paule
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- Bis(dicyanomethylene)squarate squaraines in their 1,2- and 1,3-forms: Synthesis, crystal structure and spectroscopic study of compounds containing alkali metals and tetrabutylammonium ions
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In this paper, we describe a new synthetic methodology and the spectroscopic characterization of two squaraines 1,2- and 1,3-substituted, named sodium 1,2-bis(dicyanomethylene)squarate and sodium 1,3-bis(dicyanomethylene)squarate. The squaraine species are derived from 1,2-dihydroxycyclobuten-3,4-dione, also known as squaric acid. A modification in the synthetic route has been developed in order to improve the yield in the synthesis of the 1,3-derivative: the in situ use of the 1,3-dianilinesquarate intermediate. In both cases, an excess basic medium was added to the solution containing all the reactants. These squaraines consist of a cyanine-type chromophore with high thermal stability and several different spectroscopic properties. In addition, it was made a comparative analysis based on the spectroscopic study of the 1,3- and 1,2-compounds, as well as their derivatives with several metal alkalis (K+, Rb+, Mg2+, Ca2+, Sr2+ and Ba2+), besides tetrabutylammonium ion (TBA). The vibrational spectroscopic data demonstrate the centrosymmetric structure in solid state phase of the 1,3-compound due to non-coincidence between the infrared and Raman bands in the vibrational spectra. The crystal structures were also obtained for Ca2+ and Ba2+ ions with the 1,3-isomer. These salts crystallize in different space groups, also showing very distinct coordination properties and intermolecular interactions. This study provides a sound basis for the future expansion of structural and spectroscopic investigations of this interesting group of metal-ligand compounds as building blocks systems in supramolecular chemistry.
- de Oliveira, Vanessa E.,de Carvalho, Gustavo S.,Yoshida, Maria I.,Donnici, Claudio L.,Speziali, Nivaldo L.,Diniz, Renata,de Oliveira, Luiz Fernando C.
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- The synthesis and spectroscopic studies of new aniline-based squarylium dyes
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The synthesis and spectroscopic properties of series of new aniline-based squarine dyes have been presented. The effect of solvent polarity, hydrogen bonding and substituent on spectroscopic properties of 1,3-bis(phenylamino)squarine (SQG1), 1,3-bis(4-bro
- Jurek, Katarzyna,Kabatc, Janina,Kostrzewska, Katarzyna
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- Engineering zwitterionic barrier by squaraine-based porous organic framework fiber for superior lithium-sulfur batteries
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The lithium sulfur (Li-S) battery holds great promise in next-generation energy storage technologies. However, the lithium polysulfide (LiPS) shuttle and slow reaction kinetics still limit its commercial development. Here, a squaraine-based porous organic framework (POF) with sulfophilic and lithiophilic moieties was developed as the separator modifications for the first time. The POF coating layer on the common separator builds a strong barrier against the LiPS shuttling, resulting in a robust inhibition on the shuttle effect as well as boosted sulfur reaction kinetics. Therefore, the POF-PP separator demonstrates stable cycling performance with a low capacity attenuation rate of 0.04% over 500 cycles and high areal discharge capacity of 4.67 mAh cm?2 with a sulfur loading of 5 mg cm?2, which show high potential for high loading and practical Li-S battery.
- Bakenov, Zhumabay,Zhang, Xiaojie,Zhang, Yongguang,Zhao, Jinchen,Zhao, Yan
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- Factors that influence the spectroscopic properties of 1,3-bis[p-substituted-(phenylamino)]squaraines
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The spectroscopic characteristics of a series of ten aminosquaraine dyes that differ in the type of chemical substituent at the p-position of the phenyl ring were investigated. The effect of solvent on the properties of the dyes in their ground and excite
- Kabatc, Janina,Kostrzewska, Katarzyna,Orze?, ?ukasz
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p. 226 - 232
(2016/04/04)
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- The reaction of phenylhydrazine with squaric acid: A model for carbohydrate osazone formation
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The reaction of squaric acid (1) with phenylhydrazine yields cyclobutanetetraone poly(phenylhydrazones) (2-4), as reported earlier, as well as squaric acid derivatives, reported here. The latter products are a salt, 1,3-dianilinocyclobutenediylium-2,4-dio
- El Khadem,Shalaby,Coxon,Fatiadi
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