How is 2,1,3-Benzothiadiazol-5-amine (CAS: 874-37-3) typically synthesized?

2,1,3-Benzothiadiazol-5-amine is commonly synthesized via the reaction of 1,3-benzothiazol-2-one with ammonia or amines under basic conditions. The process involves heating the 1,3-benzothiazol-2-one with excess ammonia or an amine in a non-aqueous solvent like methanol or ethanol. The yield is typically high, around 70-80%, and the reaction is conducted with a catalyst such as sodium hydroxide to enhance selectivity and yield.