67104-97-6

109-81-9

67104-97-6

General procedure for the synthesis of 2-methyl-1,2,5-thiadiazolidine 1,1-dioxide from N-methylethylenediamine: to a stirred solution of N-methylethylenediamine (1.200 g, 16.2 mmol) in pyridine (20 mL) was added sulfonamide (1.867 g, 19.4 mmol). The reaction mixture was heated to reflux in an oil bath at 120°C for 16 hours. After completion of the reaction, it was cooled to room temperature and concentrated under reduced pressure to remove the solvent. The residue was partitioned between ethyl acetate and saturated aqueous sodium chloride solution for liquid-liquid extraction. The organic layer was separated and washed sequentially with 1N aqueous hydrochloric acid and saturated aqueous sodium chloride. The organic layer was dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure to give the colorless oily product 2-methyl-1,2,5-thiadiazolidine 1,1-dioxide (0.61 g, 28% yield). The product was characterized by 1H NMR (300 MHz, CDCl3): δ 4.30 (br s, 1H), 3.53 (m, 2H), 3.40 (m, 2H), 2.76 (s, 3H).