- Modified methods for the synthesis of triazinyl fluorescent brightener intermediates
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The production of triazinyl fluorescent brightener intermediates in high yields is described. The method involves a simplified work-up for the preparation of 4-nitro-toluene-2-sulfonic acid and the use of diethylene glycol instead of water in the preparation of 4,4′-dinitrostilbene-2,2′- disulfonic acid.
- Safaei-Ghomi, Javad,Tajbakhsh, Mahmood,Bamoniri, Abdolhamid,Parach, Ali
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- Stilbene type compound as well as synthesis method and application thereof
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The invention discloses a stilbene type compound as well as a synthesis method and application thereof, wherein the synthesis method comprises the steps: taking an intermediate 2 and an intermediate 4 as initiators, sequentially carrying out Wittig reaction, reduction reaction, amino protection reaction, condensation reaction, deprotection reaction and amidation reaction, and then refining to obtain the stilbene type compound. The synthesis process is high in controllability, used reagents are low in price, and the method is simple and easy to industrialize. The stilbene type compound can be used as a medicine for resisting tumors and viruses and treating fungal infection and cardiovascular and cerebrovascular diseases.
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Paragraph 0008; 0039; 0050; 0061
(2021/07/01)
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- P-nitrotoluene-2-sulfonic acid continuous synthesis method
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Disclosed is a p-nitrotoluene-2-sulfonic acid continuous synthesis method. The p-nitrotoluene-2-sulfonic acid continuous synthesis method comprises melting or dissolving p-nitrotoluene in organic solvent or inorganic solvent, and inletting the melt of solution together with sulfur trioxide mixed gas into a film sulfonation reactor for sulfonation reaction, filtering liquid reaction products containing the inorganic solvent to remove the inorganic solvent and then feeding the reaction products into an ageing tank, or directly feeding the solvent-free or organic solvent-containing liquid reaction products into the ageing tank for stirred ageing; and performing hydrolysis by adding in deionized water to obtain hydrolyzed products, which, if containing no organic solvent, are p-nitrotoluene-2-sulfonic acid, else, performing extraction by adding in deionized water for dissolution in aqueous phase to obtain the p-nitrotoluene-2-sulfonic acid. The p-nitrotoluene-2-sulfonic acid continuous synthesis method has the advantages of being low in production cost, free from producing waste acid, high in safety performance and capable of achieving continuous production.
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Paragraph 0014; 0015; 0016; 0017; 0018; 0019; 0020-0023
(2018/10/11)
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- DSD acid preparation method
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The invention relates to the field of chemical synthesis, in particular to a DSD acid preparation method. The DSD acid preparation method includes the steps that methylbenzene is subjected to sulfonation, purification and separation to obtain OTS, wherein the byproduct is PTS; OTS is subjected to mixed acid nitration to obtain PNTS; PNTS is subjected to chlorine oxidative condensation to obtain DNS; DNS is subjected to catalyzed hydrogeneration reduction to obtain the high-quality target product, namely DSD acid which can be directly used for synthesizing a fluorescent whitening agent. The synthesis method greatly reduces dangerousness of the process, greatly reduces generation of harmful byproducts and waste, particularly, does not generate a lot of carcinogenic intermediate, namely ortho-nitrotoluene, completely solves the nitration safety problem of the old technology, and has the advantages of being simple in step, high in yield and the like.
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- Clean-chemistry sulfonation of aromatics
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A solution of TFAA/H2SO4 is an atom-efficient liquid-phase system for rapid sulfonation of aromatic structures; H2SO4 is consumed stoichiometrically and the spent trifluoroacetic anhydride (TFAA) is readily recovered as trifluoroacetic acid (TFA) which can be recycled to TFAA.
- Corby, Brian W.,Gray, Anthony D.,Meaney, Padraig J.,Falvey, Michael J.,Lawrence, Gregory P.,Smyth, Timothy P.
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p. 326 - 327
(2007/10/03)
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- Aryl sulfonic acids and derivatives as FSH antagonists
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This invention provides compounds of formula I having the structure wherein R1, Ar, Ar′, and Q are as defined in the specification, or a pharmaceutically acceptable salt thereof, which are useful as contraceptive agents.
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- Synthesis of reference substances for highly polar metabolites of nitroaromatic compounds
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Transformation processes of nitroaromatic compounds (NAC) lead to polar and highly hydrophilic metabolites. For the unequivocal identification of proposed metabolites reference substances are needed. Since most of them are not commercially available, their synthesis was done in our group. In many cases no satisfying synthesis schemes were found in the literature. In this communication, we therefore describe the preparation, structural elucidation and separation of 17 compounds. Many of the newly synthesized analytes were found in various water samples from a former ammunition plant.
- Schmidt, Torsten C.,Steinbach, Klaus,Buetehorn, Ulf,Heck, Kerstin,Volkwein, Ute,Stork, Gottfried
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p. 3119 - 3130
(2007/10/03)
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