Water → 4-(Methylamino)-3-nitrobenzoic acid

Participants

Reaction Steps

A 40% solution of methylamine in water (11 mL; 128 mmol) (or any other primary amine) was slowly added to a stirring suspension of 4-fluoro-3-nitrobenzoic acid (278, 6.1 g; 32.9 mmol) in DMF (20 mL) at room temperature. After the addition was completed the mixture was stirred at the same temperature for 60 min; concentrated in vacuo, and suspended in 5% KHSO4 (final pH=2). The suspension was stirred overnight; the precipitate was collected by filtration, washed with water, then with ether and dried to afford the title compound 279 (6.5 g; 100% yield). 1H NMR: (400.2 MHz, DMSO) δ (ppm): 12.8 (bs; 1H), 8.59 (d, J=2.0 Hz; 1H); 8.55 (q, J=5.0 Hz; 1H); 7.96 (dd, J=2.0, 9.1 Hz; 1H); 7.04 (d, J=9.1 Hz; 1H); 3.00 (d, J=5.0 Hz; 3H). MS: calc: 196.2; found: 197.1 (M+H)

Provenance & Evidence