121-03-9Relevant articles and documents
Modified methods for the synthesis of triazinyl fluorescent brightener intermediates
Safaei-Ghomi, Javad,Tajbakhsh, Mahmood,Bamoniri, Abdolhamid,Parach, Ali
, p. 318 - 321 (2003)
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.
P-nitrotoluene-2-sulfonic acid continuous synthesis method
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Paragraph 0014; 0015; 0016; 0017; 0018; 0019; 0020-0023, (2018/10/11)
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.
Clean-chemistry sulfonation of aromatics
Corby, Brian W.,Gray, Anthony D.,Meaney, Padraig J.,Falvey, Michael J.,Lawrence, Gregory P.,Smyth, Timothy P.
, p. 326 - 327 (2007/10/03)
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.