Reaction #2189

Reaction equation

4-chloro-4'-methylsulfonylmethylbenzophenone

hydrazine monohydrate

ethanol

→

desired product

Yield 97.0%

4-Chloro-4'-methylsulfonylmethyl-benzophenone-hydrazone

Yield 97.0%

Solvents

acetic acid

Conditions

Workup

1. 1
   Temperatureunder reflux
2. 2
   ConcentrationThe reaction mixture was concentrated
3. 3
   Extractionthe residue was extracted with ethyl acetate
4. 4
   WashThe ethyl acetate layer was washed with water
5. 5
   Dryingdried over anhydrous magnesium sulfate
6. 6
   workup.DISTILLATIONEthyl acetate was distilled off under reduced pressure
7. 7
   OtherThe residue was purified by silica gel column chromatography (n-hexane:ethyl acetate=2:1)

Procedure

4-chloro-4'-methylsulfonylmethylbenzophenone (10.0 g) and hydrazine monohydrate (4.9 g) were added to ethanol (200 ml) and acetic acid (10 ml), and the mixture was stirred for 6 hours under reflux. The reaction mixture was concentrated, and the residue was extracted with ethyl acetate. The ethyl acetate layer was washed with water and then dried over anhydrous magnesium sulfate. Ethyl acetate was distilled off under reduced pressure. The residue was purified by silica gel column chromatography (n-hexane:ethyl acetate=2:1) to obtain the desired product (10.0 g, melting point: 52° to 54° C., yield: 97%)

Source