2(3H)-benzoxazolone, 3-methyl-5-nitro- → 5-Amino-3-methyl-2,3-dihydro-1,3-benzoxazol-2-one

Participants

Reaction Steps

3-Methyl-5-nitro-3H-benzooxazol-2-one (22.87 g) was dissolved in acetic acid (350 mL). Palladium on activated charcoal 10% (6.27 g) was added and an atmosphere of hydrogen was introduced at r.t. The mixture was stirred over night. The reaction mixture was filtered over dicalite speed plus (Acros) and the solvent was evaporated. The residue was dissolved in 2M aqueous HCl (500 mL) and stirred for 10 minutes. The resulting solution was basified with conc. aqueous NaOH (200 mL) to pH 11 and stirred for 20 minutes at r.t. The resulting precipitate was filtered off and washed with cold water. Residual water was removed by co-evaporation with toluene. The resulting solid was dried in vacuo. The title compound was obtained as a brown solid (18.72 g, 92%). MS (m/e)=165.2 [M+H+].

Provenance & Evidence