Phosgene → 2-Methyl-4-nitrophenyl isocyanate

Participants

Reaction Conditions

Reaction Steps

2-Methyl-4-nitroaniline (35.0 g, 230 mmol) was dissolved in ethyl acetate (400 ml) and cooled to 0° C. Phosgene (180 ml, 20% in toluene) was added drop wise over 30 min, precipitation of a white salt followed instantly. After the last addition the temperature was allowed to slowly rise to room temperature, and then the reaction mixture was brought to reflux (˜100° C.). It was refluxed for 2 h 30 min, after which 200 ml of solvent was distilled off before the temperature was lowered to 80° C. and phosgene (140 ml, 20% in toluene) was added drop wise. After the last addition the reaction solution was refluxed for 3 hours, allowed to cool to room temperature and concentrated to dryness. The brown/yellow material was dissolved in diethyl ether (250 ml), filtered and concentrated to give a pale brown powder (36 g, 88%).

Provenance & Evidence