5-Amino-1,2,4-thiadiazole

943653-32-5

7552-07-0

The general procedure for the synthesis of 5-amino-1,2,4-thiadiazole from the compound (CAS: 943653-32-5) is as follows: (E)-N'-carbamoyl-N,N-dimethylformamide (3.9 g, 30 mmol), hydroxylamine-O-sulphonic acid (3.7 g, 33 mmol) were mixed with anhydrous ethanol (100 mL) and reacted by heating at 80 °C for for 8 hours. Upon completion of the reaction, the mixture was cooled to room temperature, triethylamine was added and stirring was continued at room temperature for 19 hours. Subsequently, the solvent was removed by distillation under reduced pressure, and the residue was dissolved in a mixture of dichloromethane and methanol (10 mL) with a volume ratio of 9:1. Dichloromethane solution containing 5% methanol was used as the eluent, and purification was carried out by silica gel column chromatography, resulting in 1 ,2,4-thiadiazol-5-amine as a white solid (1.4 g, 47% yield). The product was characterized by 1H NMR (400 MHz, DMSO-d6): δ 7.95 (s, 2H), 7.85 (s, 1H).LC/MS analysis conditions: 10%-99% acetonitrile (containing 0.035% trifluoroacetic acid)/water (containing 0.05% trifluoroacetic acid), observed m/z (M+1) = 102.1; retention time tR = 0.39 min.