- Preparation method of 2,6-dihydroxytoluene
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The invention discloses a preparation method of 2,6-dihydroxytoluene. The preparation method comprises the following steps of dissolving prepared 3,5-diamino-4-methylbenzoic acid in water, adding dilute sulphuric acid, stirring uniformly, adding ZnCl2, reducing the temperature to minus -2 to 2 DEG C after stirring uniformly, dropwise adding a sodium nitrite solution into the mixture, continuouslystirring to react for 5-6 hours after the dropwise adding is finished, then adding water and dilute sulphuric acid, mixing uniformly, then heating for boiling, reacting for 30-45 minutes, then addingsodium hydroxide, carrying out reflux reaction for 1-2 hours, cooling to room temperature, adding diethyl ether, stirring for 20-40 minutes, then adding zeolite, stirring and mixing for 1-2 hours, carrying out reduced-pressure distillation after filtering, and preparing the 2,6-dihydroxytoluene. The preparation method disclosed by the invention has the beneficial effects that the raw-material costis low, the operation is simple, safe and reliable, the requirements for the environmental conditions are mild, the product purity is high and the yield is high.
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Paragraph 0022-0024; 0031-0033; 0040-0042; 0049-0060
(2018/04/27)
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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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- An atom economical method for the direct synthesis of quinoline derivatives from substituted o-nitrotoluenes
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A highly efficient one-pot procedure for the preparation of substituted quinolines from substituted o-nitrotoluenes with electron-withdrawing groups and olefins (acrylic esters and acrylonitriles) using a cesium catalyst has been developed. A plausible [2+4] cycloaddition mechanism is proposed. This method uses nitroaromatic compounds as the starting materials to give quinoline derivatives in good to high yields under mild conditions with no transition metal catalysis. It provides an atom economical pathway for the synthesis of quinoline derivatives which could be used in industrial processes.
- Liu, Guiyan,Yi, Maocong,Liu, Lu,Wang, Jingjing,Wang, Jianhui
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p. 2911 - 2914
(2015/02/19)
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- Synthesis of 2-methyl-1,5-dinitro-3- and 2-methyl-1,3-dinitro-5-(trifluoromethyl)benzenes and their transformation into 6-nitro-4-(trifluoromethyl)- and 4-nitro-6-(trifluoromethyl)-1H-indoles
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A facile two-step synthesis of 2-methyl-1,5-dinitro-3- and 2-methyl-1,3-dinitro-5-(trifluoromethyl)benzenes is described. The first step is the nitration of otho- and para-methylbenzoic acids to furnish the corresponding dinitroacids. The dinitroacids then react with sulfur tetrafluoride to provide the corresponding trifluoromethylated products. The latter are easily transformed into 6-nitro-4-(trifluoromethyl)- and 4-nitro-6-(trifluoromethyl)-1H-indoles by applying the Batcho-Leimgruber synthetic protocol.
- Petruk, Oksana M.,Kyriukha, Yevhenii A.,Bezdudny, Andriy V.,Rozhkov, Vladimir V.
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p. 176 - 179
(2015/06/08)
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- FLUORO-SUBSTITUTED COMPOUNDS AS KINASE INHIBITORS AND METHODS OF USE THEREOF
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The present invention provides for novel compounds of Formula I and pharmaceutically acceptable salts and solvates thereof which have kinase inhibitor activity. The present invention further provides for pharmaceutical compositions comprising the same as well as methods of treating and preventing a Bcr-Abl, c-Kit or PDGF-R mediated disorder for which one or more kinase inhibitor is indicated, including neoplasia such as chronic myelogenous leukemia or gastrointestinal stromal tumors. The present invention also provides for processes of making the compounds of Formula I, including salts and solvates thereof, and pharmaceutical compositions comprising the same.
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Page/Page column 25
(2011/02/24)
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- PROLYL HYDROXYLASE INHIBITORS
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The invention described herein relates to certain 2,4-dioxo-l,2,3,4-tetrahydro-7- quinazolinecarboxamide derivatives of formula (I) which are antagonists of HIF prolyl hydroxylases and are useful for treating diseases benefiting from the inhibition of this enzyme, anemia being one example.
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Page/Page column 16-17
(2010/07/10)
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- Derivatives of 4-sulfanylalkyl-3,5-dinitrobenzyl alcohol and method for preparing the same
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The present invention is directed to a novel 4-sulfanylalkyl-3,5-dinitro benzyl alcohol compound and its preparation method, more specifically, derivatives of 4-sulfanylalkyl-3,5-dinitro benzyl alcohol compound having the following formula 1 and its preparation method: wherein, R is hydrogen, alkyl group, or acetyl group, and n is an integer of 1 to 25. The organic compound of the present invention can be used as a material for molecular electronic device.
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- Process for the production of nitro derivatives of aromatic compounds
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Nitroderivates of aromatic compounds which are difficult to nitrate, can readily be obtained by nitration providing that the aromatic compound is treated with nitric acid or another nitrating agent in the presence of aliphatic or cycloaliphatic hydrocarbons monosubstituted or polysubstituted by halogen, the nitro group or an alkyl sulphonyl group, and the nitro derivative formed subsequently isolated.
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