反应详情

To a mixture of 2.4 g of 10-chloro-2-(4-chlorophenyl)-5,6-dihydro-[1]benzothiepino[5,4-c]pyridazin-3(2H)-one, prepared in Example 11 in 25 ml of water and 300 ml of acetone is added 2.8 g of sodium hypobromite trihydrate. The mixture is stirred for 18 hours at room temperature and concentrated under reduced pressure. To the residue is added water, the precipitated crystals are collected by filtration and recrystallized from dimethylformamide-water to give 1.0 g of 10-chloro-2-(4-chlorophenyl)-5,6-dihydro-[1]benzothiepino[5,4-c]-pyridazin-3(2H)-one 7-oxide, melting at 239°-241° C. with decomposition.

1. concentrationconcentrated under reduced pressure
2. additionTo the residue is added water
3. filtrationthe precipitated crystals are collected by filtration
4. customrecrystallized from dimethylformamide-water