Acetic Acid → methyl 4-amino-2-(N-tert-butylsulfamoyl)benzoate

Participants

Reaction Conditions

Reaction Steps

50.0 g (0.158 mol) of methyl 2-(N-tert-butylsulfamoyl)-4-nitrobenzoate (prepared in accordance with DE-OS 4 236 902) are added to a mixture of 180 ml of acetic acid and 75 ml of water and the mixture is heated to 80° C. 26.5 g (0.474 mol) of iron powder are added in portions such that the temperature does not rise above 85° C. The mixture is then stirred at 80° C. for 4 hours, 85 ml of 2N HCl are added at this temperature and the mixture is allowed to cool to 25° C. The solid is filtered off and washed thoroughly with water. It is then extracted hot 3 times with 250 ml of ethyl acetate each time. The ethyl acetate phase is evaporated and the residue is triturated with diisopropyl ether and dried. 37.7 g (83% of theory) of methyl 4-amino-2-(N-tert-butylsulfamoyl)benzoate of melting point 198-199° C. are obtained.

Provenance & Evidence