| production method | This product is prepared by using quinoline as raw material through the following steps. 275ml of industrial chlorosulfonic acid was cooled to 10-20 °c with stirring, and 75g of quinoline was added dropwise for about 1-1.5h. Heated to 135-145 °c for 6h under reflux, large amounts of hydrogen chloride were initially evolved. After completion of the reaction, the reaction mixture was cooled to room temperature, and the reaction mixture was poured into ice, diluted with water to precipitate a yellow-brown precipitate, and filtered to obtain 70-80g of a wet product of quinoline-8-sulfonyl chloride. Take the above quinoline -8-sulfonyl chloride pure product 25g, dissolve in 80ml concentrated hydrochloric acid, filtration, filtrate cooling. Then, 80g of stannous chloride dissolved in 200ml of concentrated hydrochloric acid was added dropwise to the cold solution, and yellow crystals were precipitated by heating. It is cooled well, filtered and washed well with 1:1 cold hydrochloric acid. The crude product was dissolved in sodium hydroxide solution and neutralized with 1:1 hydrochloric acid to precipitate to give pure magenta needle-like dihydrate. |
