Reaction #927278

Reaction equation

N-{3-nitro-4-(3,5-bis-trifluoromethyl-benzylamino)-phenyl}-benzenesulphonamide

Na2S2O4

→

N-{3-amino-4-(3,5-bis-trifluoromethyl-benzylamino)-phenyl}-benzenesulphonamide

Solvents

water

methanol

water

Conditions

Workup

1. 1
   TemperatureThe mixture is refluxed
2. 2
   Otherthis takes about 1 h
3. 3
   TemperatureAfter cooling the mixture
4. 4
   workup.DISTILLATIONAbout 100 mL of the methanol/water mixture are distilled off
5. 5
   Temperaturethe resulting solution is cooled
6. 6
   Otherthe crystals precipitated
7. 7
   Filtrationare filtered off
8. 8
   Washwashed with water
9. 9
   workup.DISSOLUTIONThe crystals are dissolved in ethyl acetate
10. 10
    Otherdried
11. 11
    Otherevaporated down until not
12. 12
    Otherquite dry
13. 13
    TemperatureAfter cooling the crystals
14. 14
    Otherprecipitated
15. 15
    Filtrationare filtered off
16. 16
    Washwashed with diethylether

Procedure

N-{3-nitro-4-(3,5-bis-trifluoromethyl-benzylamino)-phenyl}-benzenesulphonamide (8.6 g, 16.6 mmol) in 200 mL methanol are refluxed and within 0.5 h combined with a solution of Na2S2O4 (14.2 g, mmol) in 50 mL water. The mixture is refluxed until totally decolorised (this takes about 1 h). After cooling the mixture is diluted with water. About 100 mL of the methanol/water mixture are distilled off, the resulting solution is cooled, the crystals precipitated are filtered off and washed with water. The crystals are dissolved in ethyl acetate, dried and evaporated down until not quite dry. After cooling the crystals precipitated are filtered off and washed with diethylether.

Source