Cas:108-33-8,timtec-Bb Sbb000045

1) In a dry mortar, 0.05 mol of aminothiourea was added, followed by 0.055 mol of glacial acetic acid, 0.055 mol of silica and 0.25 mol of phosphorus oxychloride. The mixture was ground at room temperature for 10 minutes. The progress of the reaction was monitored by thin-layer chromatography (TLC) using a mixed solvent of ethyl acetate and petroleum ether in a volume ratio of 1:3 as the developing agent until the spot of the starting material aminothiourea disappeared, indicating the completion of the reaction. After standing for 30 minutes, the crude product was obtained. 2) The crude product was transferred to a beaker and 5% sodium carbonate solution was added to adjust the pH to 8. The mixture was filtered under reduced pressure, and the filter cake was dissolved in N,N-dimethylformamide (DMF) to remove silica. The filtrate was concentrated under reduced pressure, and the solvent was removed. The product was washed with water and filtered under reduced pressure to obtain 2-amino-5-methyl-1,3,4-thiadiazole with a yield of 95.2%.