88-53-9Relevant articles and documents
Method for preparing CLT acid by taking m-toluidine as raw material
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Paragraph 0053; 0059-0060, (2019/12/02)
The invention discloses a method for preparing CLT acid by taking m-toluidine as a raw material, and belongs to the field of chemical synthesis. The method solves the problems that existing CLT acid production is low in yield, not environmentally friendly and the like. The method comprises: S01) an acylation step, namely a step of reacting m-toluidine and acetic anhydride to obtain acylation reaction solution; S02) a chlorination step, namely a step of adding acetic acid and concentrated hydrochloric acid into the acylation reaction solution, then adding hydrogen peroxide, and finally adding an aqueous solution containing sodium sulfite to obtain a chlorination reaction solution; S03) a hydrolyzing step to form salt, namely a step of adding concentrated sulfuric acid into the chlorinationreaction solution, and removing the solvent after reaction; S04) a transposition sulfonation step, namely a step of adding chlorobenzene into the solvent-removed reaction solution obtained in the stepS03, heating the mixture, adding dichlorobenzene, heating the mixture again, reacting the mixture for 7-10 hours with the temperature of the system being maintained at a temperature higher than 170 DEG C, and stopping heating; and S05) a step of post-treatment to obtain a finished product that is the CLT acid. The method has the advantages of environmental protection and the like.
Method for achieving pipe-type continuous production of CLT acid nitride
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Paragraph 0079, (2016/11/17)
The invention discloses a method for achieving pipe-type continuous production of CLT acid nitride. The method comprises the steps that 1, methylbenzene and sulfuric acid conduct a sulfonation reaction in a sulfonation pipe reactor; 2, thth sulfonation reaction solution obtained in the first step and chlorine are continuously fed into a chlorination pipe reactor for a chlorination reaction; 3, the chlorination reaction solution obtained in the second step and nitric acid are continuously fed into a nitrification pipe reactor for a nitrification reaction, and then the CLT acid nitride is prepared. According to the method for achieving pipe-type continuous production of the CLT acid nitride, purification treatment does not need to be conducted on an intermediate in the reaction process, operation is easy, the reaction efficiency is high, and the objective product selectivity is high.
Process for the preparation of aminoarylsulphonic acids in sulfolene solvent
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, (2008/06/13)
Aromatic aminosulphonic acids which have a reduced content of discoloring by-products are obtained when aromatic amines are reacted with a sulphonating agent in a reaction medium at least some of which consists of tetramethylene sulphone.