A process for the preparation of a 3-hydrazino-1, 2-benzisothiazole 1,1-dioxide of the formula ##STR1## in which R.sup.1 and R.sup.2 each independently is hydrogen, alkyl, halogen, amino, hydroxyl or carboxyl, and R.sup.3 and R.sup.4 each independently is hydrogen, alkyl, cycloalkyl or aryl, comprising reacting a 3-keto-2H,3H-1,2-benzisothiazole 1,1-dioxide of the formula ##STR2## with a hydrazine of the formula ##STR3## in a molar ratio of 1:1 to 1:50, in an inert solvent, at a temperature between 75.degree. C. and 200.degree. C. and for a reaction time of 15 to 40 hours. The products, some of which are known, are fungicidally active and can also be used as intermediates.
一种制备式为##STR1##的3-
肼基-1,2-苯并
异噻唑-1,1-二氧化物的方法,其中R.sup.1和R.sup.2各自独立地为氢、烷基、卤素、
氨基、羟基或羧基,而R.sup.3和R.sup.4各自独立地为氢、烷基、环烷基或芳基,包括在惰性溶剂中,将式##STR2##的3-酮基-2H,3H-1,2-苯并
异噻唑-1,1-二氧化物与式##STR3##的
肼反应,摩尔比为1:1至1:50,在75℃至200℃的温度下反应15至40小时。其中一些产物具有杀真菌活性,并且也可用作中间体。