Reaction #63464

Reaction equation

4-(3,4-Dihydro-3-oxo-1,4[2H]-benzothiazin-6-yl)-4-oxobutyric acid

hydrazine

→

title compound

6-(3,4-Dihydro-3-oxo-1,4[2H]-benzothiazin-6-yl)-2,3,4,5-tetrahydropyridazin-3-one

Solvents

ethanol

Conditions

Workup

1. 1
   TemperatureThe mixture was heated
2. 2
   Temperatureat reflux for three hours
3. 3
   Temperaturecooled slowly
4. 4
   FiltrationFiltration

Procedure

4-(3,4-Dihydro-3-oxo-1,4[2H]-benzothiazin-6-yl)-4-oxobutyric acid (2.0 g) was suspended in 60 ml of ethanol and 1 ml of hydrazine added. The mixture was heated at reflux for three hours, then cooled slowly. Filtration gave 1.85 g of the title compound, mp 299°-302° C.

Source