Piperazine → HCID 178527169, compound

Participants

Reaction Steps

To a stirred solution of 3.4 g of anhydrous piperazine in 25 ml of methanol is added 5.0 g of 3,7-dichloro-2H-1,2,4-benzothiadiazine 1,1-dioxide, while the mixture is cooled in an ice bath. After the addition, the mixture is stirred at room temperature for 3 hours. The crystalline precipitate is collected by suction filtration and treated with a mixture of 2 ml of concentrated hydrochloric acid and 40 ml of water. After removal of the insoluble materials by suction filtration, the filtrate is adjusted to a pH 8.0 with a dilute aqueous sodium hydroxide solution to give 3.9 g of the desired product, m.p. 292°-295° C. (decomposition).

Provenance & Evidence