2.4- Disulfamyl-5-chloroaniline

A) Preparation of 3-Chloromethyl-6-Chloro-7-Sulfamyl-3,4-Dihydro-Benzothiadizine-1,1-Dioxide - To 8 ml of 40-50% chloroacetaldehyde aqueous solution and 7 ml of dimethylformamide are added 10 grams of 2,4-disulfamyl-5-chloroaniline. The mixture is heated on a steam bath for 2 hours after which it is concentrated at reduced pressure. The residue is triturated with water. The solid material is recrystallized from methanol-ether after treatment with activated carbon to give 7.2 grams of product, MP 229°-230°C. 

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