- 5-Nitroisophthalic acid hydrate
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In the title compound, C8H5NO6·H2O, the carboxylic acid groups are coplanar with the phenyl ring, whereas the nitro group is twisted from it by 26.1 (3)°. In the crystal, the molecules are linked by O - H...O hydrogen bonds through the water molecules and by weak C -H...O hydrogen bonds involving the nitro groups, to form infinite zigzag sheets.
- Mahapatra, Ajit Kumar,Adak, Avijit,Goswami, Shyamaprosad,Nigam, Gur Dayal,Chinnakali, Kandasamy,Shanmuga Sundara Raj,Razak, Ibrahim Abdul,Fun, Hoong-Kun
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- Continuous synthesis method of 5-nitroisophthalic acid
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The invention relates to a continuous synthesis method of 5-nitroisophthalic acid. The method is characterized by comprising the following steps: by using isophthalic acid feed liquid and a nitrationreagent as raw materials, carrying out preheating, nitration reaction and quenching to obtain 5-nitroisophthalic acid; the synthesis method is carried out in a continuous reactor, raw materials are uninterruptedly added into a feed port of the continuous reactor, the 5-nitroisophthalic acid is uninterruptedly obtained at a discharge port of the reactor, and the total reaction time is less than orequal to 20 minutes; the phthalic acid feed liquid can be a solution, an emulsion, turbid liquid or an emulsion. According to the method, the limitation of the traditional process is innovatively broken through, and the continuous synthesis of the 5-nitroisophthalic acid is realized; and the total reaction time is greatly shortened, the material amount in the reactor is greatly reduced, and the safety is greatly improved.
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Paragraph 0050; 0051
(2020/12/10)
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- Synthesizing method of 5-nitroisophthalic acid
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The invention discloses a synthesizing method of 5-nitroisophthalic acid. The synthesizing method comprises the following steps of reacting, washing by water, filtering, recrystallizing and purifying.The synthesizing method has the advantages that by using isophthalic acid as a raw material, a small amount of concentrated sulfuric acid and 60% of nitric acid are used for reacting and nitrifying,so as to synthesize the 5-nitroisophthalic acid; the usage amounts of sulfuric acid and nitric acid are reduced, the effective utilization rate of equipment is improved, the generation of waste liquidin production is reduced, the difficulty in treatment of the waste liquid is decreased, the problem of nitrifying difficulty is solved, and the economic benefit and environment-friendly social benefit of the product are improved.
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Paragraph 0025; 0027; 0029; 0031; 0033; 0034; 0035; 0036
(2018/04/03)
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- Liquid-Crystalline Star-Shaped Supergelator Exhibiting Aggregation-Induced Blue Light Emission
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A family of closely related star-shaped stilbene-based molecules containing an amide linkage are synthesized, and their self-assembly in liquid-crystalline and gel states was investigated. The number and position of the peripheral alkyl tails were systematically varied to understand the structure-property relation. Interestingly, one of the molecules with seven peripheral chains was bimesomorphic, exhibiting columnar hexagonal and columnar rectangular phases, whereas the rest of them stabilized the room-temperature columnar hexagonal phase. The self-assembly of these molecules in liquid-crystalline and organogel states is extremely sensitive to the position and number of alkoxy tails in the periphery. Two of the compounds with six and seven peripheral tails exhibited supergelation behavior in long-chain hydrocarbon solvents. One of these compounds with seven alkyl chains was investigated further, and it has shown higher stability and moldability in the gel state. The xerogel of the same compound was characterized with the help of extensive microscopic and X-ray diffraction studies. The nanofibers in the xerogel are found to consist of molecules arranged in a lamellar fashion. Furthermore, this compound shows very weak emission in solution but an aggregation-induced emission property in the gel state. Considering the dearth of solid-state blue-light-emitting organic materials, this molecular design is promising where the self-assembly and emission in the aggregated state can be preserved. The nonsymmetric design lowers the phase-transition temperatures.The presence of an amide bond helps to stabilize columnar packing over a long range because of its polarity and intermolecular hydrogen bonding in addition to promoting organogelation.
- Pathak, Suraj Kumar,Pradhan, Balaram,Gupta, Monika,Pal, Santanu Kumar,Sudhakar, Achalkumar Ammathnadu
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p. 9301 - 9312
(2016/10/06)
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- Synthesis of bis(propargyl) aromatic esters and ethers: A potential replacement for isocyanate based curators
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This study reports the synthesis and characterization of a novel class of non-isocyanate curing agents based on bis-propargyl aromatic esters 2a-e and ethers 4a-c. A total of eight non-isocyanate curators were prepared from the reaction of respective dicarboxy or dihydroxybenzene with propargyl bromide in the presence of potassium carbonate with good yields. The structure and purity of the synthesized compounds and the corresponding intermediates were confirmed by spectral (IR and NMR), thermal (DSC) and chromatographic techniques (HPLC & GC-MS). Furthermore, kinetics of the curing reaction between glycidyl azide polymer (GAP) and the synthesized alkynes (4b, 4c) were studied using time-resolved FT-IR spectroscopy as a function of time at 303, 323 and 333 K. It was found that the curing reaction was faster when the temperature was increased. Kinetic parameters of the curing reaction, such as the reaction order and activation energy, were calculated for the GAP-4a and GAP-4c systems. All the curing reactions followed first order kinetics and the corresponding activation energy of the curing reaction for the systems was found to be 15.56 and 13.22 kcal mol-1. For comparison, curing studies were performed for GAP with a conventional curator Desmodur N-100. GAP cured with non-isocyanate curators offered good mechanical properties compared to GAP cured with isocyanate (N-100). The advantage of these new curing systems is that they do not require catalyst and there is no need for specific environmental conditions. Based on these studies, 1,4-bis(2-propynyloxy)benzene (4b) has the most potential as a non-isocyanate curator for azide polymeric binders.
- Sonawane, Sanjeevani H.,Anniyappan,Athar, Javaid,Banerjee, Shaibal,Sikder, Arun K.
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p. 8495 - 8502
(2016/02/05)
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- Inclusion complex containing epoxy resin composition for semiconductor encapsulation
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The invention is an epoxy resin composition for sealing a semiconductor, including (A) an epoxy resin and (B) a clathrate complex. The clathrate complex is one of (b1) an aromatic carboxylic acid compound, and (b2) at least one imidazole compound represented by formula (II): wherein R2 represents a hydrogen atom, C1-C10 alkyl group, phenyl group, benzyl group or cyanoethyl group, and R3 to R5 represent a hydrogen atom, nitro group, halogen atom, C1-C20 alkyl group, phenyl group, benzyl group, hydroxymethyl group or C1-C20 acyl group. The composition has improved storage stability, retains flowability when sealing, and achieves an effective curing rate applicable for sealing delicate semiconductors.
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- Naaladase inhibitors for treating retinal disorders and glaucoma
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The present invention relates to pharmaceutical compositions and methods for treating a retinal disorder or glaucoma using NAALADase inhibitors.
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- Naaladase inhibitors for treating amyotrophic lateral sclerosis
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The present invention relates to pharmaceutical compositions and methods for treating amyotrophic lateral sclerosis using NAALADase inhibitors.
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- Benzenedicarboxylic acid derivatives
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New benzenedicarboxylic acid derivative compounds; pharmaceutical compositions, diagnostic methods, and diagnstic kits that include those compounds; and methods of using those compounds for inhibiting NAALADase enzyme activity, detecting diseases where NAALADase levels are altered, effecting neuronal activity, effecting TGF-β activity, inhibiting angiogenesis, and treating glutamate abnormalities, neutopathy, pain, compulsive disorders, prostate diseases, cancers, and glaucoma.
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- Process for introducing a carboxyl group to an aromatic carboxylic acid or a derivative thereof
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Disclosed is a process for introducing a carboxyl group to an aromatic carboxylic acid or a derivative thereof, which comprises reacting a starting aromatic carboxylic acid, such as a benzoic acid, a biphenylcarboxylic acid, a naphthalenecarboxylic acid, a diphenylcarboxylic acid, or a derivative thereof, with a carbon tetrahalide in the presence of a cyclodextrin and an alkali metal hydroxide, thereby introducing a carboxyl group to the aromatic ring of the starting aromatic carboxylic acid or the derivative thereof in substitution for a hydrogen atom bonded thereto. By the process of the present invention, a desired aromatic polycarboxylic acid or a derivative thereof can be easily obtained with high selectivity.
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- Electrophilic Aromatic Substitution. Part 37. Products of Aromatic Nitrations of some Chloronitrobenzenes and Substituted Benzoic Acids in Solutions of Dinitrogen Pentaoxide and of Nitronium Salts in Nitric Acid
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Yields of aromatic products of nitration in nitric acid solutions containing dinitrogen pentaoxide or nitronium salt have been determined.Evidence for the intrusion of a mechanism other than the normal nitronium ion one comes from comparison of products in the two media and from the observation of 15N NMR CIDPN effects.The additional mechanism operative with some substrates in concentrated solutions of dinitrogen pentaoxide is postulated to be one in which reversible addition of the NO3 radical is followed by combination with NO2.Dienes produced in this way can give aromatic nitroproducts by elimination of nitric acid.Nitrodecarboxylation of substituted benzoic acids occurs by a radical process.
- Moodie, Roy B.,Sanderson, Andrew J.,Willmer, Richard
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p. 645 - 650
(2007/10/02)
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- Synthesis and Spectral Characterization of Blue Dyes of the Benzene Series
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53 Donor-acceptor substituted azo dyes of the benzene series were prepared by diazonium-coupling reactions (1a-s) or halogen-cyanide exchange (->2a-x, 3a-j).Described are the preparation of the amines 4a-m and the coupling compounds 5a-t and the procedure of diazotizing and coupling.The colouristic and spectroscopic data show that compounds of the general formula 1 are excellent brilliant blue azo dyes usefull for dyeing polyester material.
- Thiel, W.,Mayer, R.,Jauer, E.-A.,Modrow, H.,Dost, H.
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p. 497 - 514
(2007/10/02)
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