- Study of Y-shaped liquid crystalline materials with polar nitro substituent
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A new homologous series of Y-shaped liquid crystals namely 4-Nitro-[2′4′bis (4″-n-alkoxybenzoyloxy)] phenyl bisazobenzenes have been synthesized and its thermotropic properties studied on the hot stage of a polarizing microscope. The compounds consist four phenyl rings joined through ester and bisazo linkages with alkoxy and nitro as terminal substituents. The structures of synthesized compounds were confirmed by spectroscopic techniques such as FTIR, 1HNMR as well as elemental analysis. The compounds were found to exhibit enantiotropic nematic and smectic mesophases. The role of molecular shape, size and polarity of functional groups in the mesophases formation is discussed.
- Dixit, Sandhya
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- Azo type dye and dye liquid crystal composition
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The invention relates to an azo type dye and a dye liquid crystal composition. The azo type dye has a structural formula as shown in specification. The azo type dye can brilliantly display characters, has good stability in mixing with liquid crystals and good dissolvability in the liquid crystals, and is extensively applicable to mixed liquid crystal materials.
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- Nano-CuFe2O4-supported sulfonic acid as a novel and recyclable nanomagnetic acid for diazotization of aromatic amines: efficient synthesis of various azo dyes
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Abstract: A novel heterogeneous sulfonic acid functionalized nanomagnetic CuFe2O4 was successfully prepared and characterized by analyzing different obtained data including Fourier transform infrared spectroscopy, X-ray powder diffraction, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, thermogravimetric analysis, dynamic light scattering and vibrating sample magnetometer. Then the novel acidic reagent was examined in synthesis of various azo-containing compounds from coupling of aryl diazonium ferrite sulfate salts with aromatic and non-aromatic compounds. The procedure starts by diazotization of aromatic amines with NaNO2 and wet CuFe2O4–SO3H and then coupling reaction of aryl diazonium ferrite sulfate salts with appropriate reagent. The prepared nano-solid acid showed high activity in synthesis of variety of aryl diazonium salts. In addition the as-prepared aryl diazonium ferrite sulfate salts are stable at room temperature for many hours and reacted efficiently in coupling reactions of aryl diazonium salts. All the azo dyes are synthesized in high yields and simple reaction conditions at room temperature. Moreover, the nanomagnetic solid acid was easily recovered from the reaction mixture and reused five runs without significant loss of activity. Graphical Abstract: [Figure not available: see fulltext.]
- Nemati, Firouzeh,Elhampour, Ali,Natanzi, Mahshid B.,Sabaqian, Samaneh
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p. 1045 - 1054
(2016/05/02)
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- 3,5-dimethylthio-2,4-bis(4,4'-dinitroazophenylaminoazo)toluene, preparation method and applications thereof
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The invention belongs to the technical field of bis triazene compounds. In the prior art, the reagent for heavy metal ion detection has low sensitivity and the selectivity is not ideal. With the present invention, the problems in the prior art can be solved. According to the present invention, with the diazotization reaction and the coupling reaction, 3,5-dimethylthio-2,4-diaminotoluene and p-aminonitro azobenzene are adopted as the raw materials to synthesize the novel bis triazene reagent, wherein the synthesized bis triazene reagent is the luminosity analysis reagent with characteristics of high sensitivity and good selectivity, and is the fluorescent reagent having the strong fluorescence characteristic.
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Paragraph 0019
(2017/08/25)
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- Carboxyl and nitrite functionalized graphene quantum dots as a highly active reagent and catalyst for rapid diazotization reaction and synthesis of azo-dyes under solvent-free conditions
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Carboxyl and nitrite functionalized graphene quantum dots was prepared from carboxyl and hydroxyl functionalized graphene quantum dots using NaNO2 in the absence of mineral acids. This functional group conversion was confirmed by FT-IR spectroscopy, photoluminescence and X-ray diffraction. The carboxyl and nitrite functionalized graphene quantum dots was used as an effective nitrosonium ion source and reusable catalyst for the efficient diazotization of a variety of arylamines without using any additional acid. Subsequent azo-coupling of these freshly prepared diazonium salts with a range of active aromatic compounds led to the requisite azo-dyes in excellent yields in very short reaction times with a simple experimental procedure.
- Valizadeh, Hassan,Shomali, Ashkan,Nourshargh, Saideh,Mohammad-Rezaei, Rahim
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p. 522 - 528
(2015/03/18)
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- A novel procedure to synthesize 3-chloro-1-(4a,10b-diazaphenanthrene-2-yl)- 4-phenyl azetidin-2-ones and exploration of their anti-inflammatory activity
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Some new derivatives of 3-chloro-1-(4a,10b-diazaphenanthrene-2-yl)-4-phenyl azetidin-2-one were synthesized through the reaction of N-{4-[phenyldiazenyl] phenyl}-N-[phenyl methylene] amine with 4-[phenyldiazenyl] aniline. The resulting 3-chloro-4-phenyl-1-{4-[phenyldiazenyl] phenyl} azetidin-2-one intermediate in benzene was irradiated in a Pyrex vessel with 350 nm UV light in a photochemical reactor to give the desired derivatives (4a-j). Structures of the new compounds were verified on the basis of spectral and elemental methods of analyses. Nine of the prepared compounds were tested for their anti-inflammatory effects; most of these compounds showed potent and significant results compared with indomethacin.
- Sharma, Manisha,Maheshwari, Arti,Bindal, Nitin
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p. E116-E120
(2013/06/04)
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- A new nitrite ionic liquid (IL-ONO) as a nitrosonium source for the efficient diazotization of aniline derivatives and in-situ synthesis of azo dyes
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A new task-specific nitrite containing ionic liquid derived from the O-nitrosation of N-methyl-N-hydroxybutylimidazolinium chloride was synthesized and used as a source of nitrosonium ion to affect the efficient diazotization of arylamines. The diazonium salts thus obtained were coupled, using standard experimental procedures, to a range of tertiary anilines, phenols and naphthols to afford the requisite azo dyes in good yield. The diazotization and subsequent azo-coupling generated the related azo dyes at 0-5 °C in short reaction times with a simple experimental procedure.
- Valizadeh, Hassan,Shomali, Ashkan
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experimental part
p. 1138 - 1143
(2012/03/27)
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- Ionic liquid 1-(3-trimethoxysilylpropyl)-3-methylimidazolium nitrite as a new reagent for the efficient diazotization of aniline derivatives and in situ synthesis of azo dyes
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A new ionic liquid 1-(3-trimethoxysilylpropyl)-3-methylimidazolium nitrite was synthesized. This ionic liquid was used as a convenient nitrosonium source in diazotization of arylamines into their corresponding diazonium salts which were converted into their related azo dyes via the in situ azo-coupling with aniline derivatives or phenolic compounds. The diazotization of anilines in this ionic liquid and subsequent azo-coupling generated the related azo dyes in good to excellent yields at 0-5 °C in short reaction times via a simple experimental procedure.
- Valizadeh,Amiri,Shomali,Hosseinzadeh
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experimental part
p. 495 - 501
(2012/07/13)
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- Role of Intermolecular Reactions in Thermolysis of Aromatic Nitro Compounds in Supercritical Aromatic Solvents
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Several nitroarenes were decomposed isothermally in dilute supercritical solution in benzene or toluene and in the vapor phase in the temperature range of 290-380 deg C in sealed glass tubes with pressure up to 100 MPa.The mechanisms of thermolysis are inferred from kinetic studies and product analysis.The initial rate-controlling step for nitrobenzene and p-nitrotoluene decomposition is probably intermolecular hydrogen abstraction to form an ArNO2H radical intermediate.The nature of the transition state is deduced from the activation volume (ΔV*), H/D kinetic-isotope effect, and a linear free-energy relationship between the ionization potential of the hydrogen donor and the logarithm of the decomposition rate.A concurrent pathway for o-nitrotoluene is an intramolecular reaction in which anthranil is an intermediate.The behavior of 1,3-dinitrobenzene and 1,4-dinitrobenzene resembles that of nitrobenzene, whereas 2,4-dinitrotoluene and 2,6-dinitrotoluene decompose in the same manner as o-nitrotoluene.Activation parameters are given and detailed mechanisms proposed.
- Minier, Leanna M.,Brower, Kay R.,Oxley, Jimmie C.
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p. 3306 - 3314
(2007/10/02)
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- THIOSULFONIC ACIDS. XXXI. ARYLAZOARENETHIOSULFONATES
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Arylazoarenethiosulfonates were obtained, and their structures and chemical characteristics were studied.It was shown that arylazoarenethiosulfonates have a nonionic structure, and this explains their high stability.It was established that they enter with difficulty into reactions with the release of nitrogen, but they enter readily into azo-coupling and reduction reactions.
- Boldyrev, B. G.,Grivnak, L. M.
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p. 324 - 330
(2007/10/02)
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