Sulfuric Acid → 4-(Methylamino)-3-nitrobenzoic acid
Reaction equation
Cl[C:2]1[CH:10]=[CH:9][C:5]([C:6]([OH:8])=[O:7])=[CH:4][C:3]=1[N+:11]([O-:13])=[O:12].[CH3:14][NH2:15].S(=O)(=O)(O)O>>[CH3:14][NH:15][C:2]1[CH:10]=[CH:9][C:5]([C:6]([OH:8])=[O:7])=[CH:4][C:3]=1[N+:11]([O-:13])=[O:12]Participants
Procedure
300 g (1.49 mol) of 4-chloro-3-nitrobenzoic acid were suspended in 836 mL of a 25-30% aqueous solution of methylamine. After heating to reflux temperature, an orange solution was obtained. The solution was kept at reflux temperature for 4 hours. The solution was cooled to room temperature, and pH was adjusted to about 2 by addition of 2M aqueous sulphuric acid. Precipitation of an orange solid was observed, which was isolated by filtration. The filtered cake was washed with 1.5 L of water and subsequently with 750 mL of ethanol. The solid was suspended in 1.6 L of ethanol and stirred at reflux temperature for 30 minutes. After cooling to room temperature, the solid was filtered and dried at 60° C. under vacuum to obtain 285 g of 4-(methylamino)-3-nitrobenzoic acid as an orange powder. Yield: 97.5%. Purity (HPLC, method 2): 97.7%.
Workup
- temperatureAfter heating
- temperatureto reflux temperature
- customan orange solution was obtained
- temperatureat reflux temperature for 4 hours
- customPrecipitation of an orange solid
- customwhich was isolated by filtration
- washThe filtered cake was washed with 1.5 L of water and subsequently with 750 mL of ethanol
- temperatureat reflux temperature for 30 minutes
- temperatureAfter cooling to room temperature
- filtrationthe solid was filtered
- customdried at 60° C. under vacuum
Sources & evidence
- ORD record
- ord-2863f9fa28fc4a3199fcb8db57b83251
- Source dataset
- uspto-grants-2015_07
- Patent number
- US09086390B2
Reaction notes
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