Reaction #1598

Reaction equation

4-benzoylbutyric acid

hydrazine

water

→

desired product

Yield 39.0%

7-phenyl-1,2-diazapin-3-one

Yield 39.0%

Solvents

toluene

toluene

Et2O

Conditions

Workup

1. 1
   workup.ADDITIONwas added in one portion
2. 2
   Temperaturethe reaction was heated
3. 3
   TemperatureThe reaction mixture was cooled
4. 4
   Washwashed with H2O (100 ml) and brine (100 ml)
5. 5
   ExtractionThe ether extract
6. 6
   Dryingwas dried over anhydrous MgSO4
7. 7
   Filtrationfiltered
8. 8
   Otherto yield an orange semisolid which
9. 9
   Otherwas triturated with ether

Procedure

To a mixture of 10 g (0.052 mole) of 4-benzoylbutyric acid in 300 ml of toluene, hydrazine was added in one portion and the reaction was heated to reflux until all water had ceased to azeotrope. The reaction mixture was cooled and the toluene was stripped off in vacuo. The residue was dissolved in 200 ml Et2O and washed with H2O (100 ml) and brine (100 ml). The ether extract was dried over anhydrous MgSO4, filtered and stripped to yield an orange semisolid which was triturated with ether to yield 3.8 g (39%) of the desired product as a yellow solid.

Source