4-Nitroaniline → ethyl N-(4-aminophenyl)carbamate
Reaction equation
[N+:1]([C:4]1[CH:10]=[CH:9][C:7]([NH2:8])=[CH:6][CH:5]=1)([O-])=O.C(N(C(C)C)CC)(C)C.[C:20]([O:23][CH2:24][CH3:25])(=[O:22])C>>[CH2:24]([O:23][C:20](=[O:22])[NH:1][C:4]1[CH:10]=[CH:9][C:7]([NH2:8])=[CH:6][CH:5]=1)[CH3:25]Participants
4
Procedure
4-Nitro-aniline (100 g, 0.72 mol) is dissolved in ethyl acetate (800 mL) and diisopropylethylamine (89.6 mL, 0.936 mol) is added. Ethyl chloroformiate (252 mL, 1.45 mol) dissolved in ethyl acetate (200 mL) is added and the solution is stirred for 18 h at ambient temperature. The mixture is washed with 2M HCl (300 mL) and brine (300 mL), dried (MgSO4) and concentrated in vacuo to half of the original volume. To the resulting solution is added palladium on activated carbon (10 g, 5% Pd, 50% H2O) and the mixture is hydrogenated on a Parr apparatus (pH2=3 bar) at ambient temperature for 12 hours. The mixture is filtered through Celite and the solvent evaporated in vacuo to give 118 g (90%) of the title compound as crystalline product.