1,2-Dichloroethane → 2-Amino-N-methyl-3-nitrobenzamide

Participants

Reaction Steps

2-Amino-3-nitro-benzoic acid (1.8 g, 9.9 mmol) and methylamine hydrochloride (1.33 g, 19.8 mmol), were stirred in dry CH2Cl2 (30 ml)/DMF (5 mL) at 0° C. EDC (2.83 g, 14.8 mmol) and DIEA (4.92 mL, 27.7 mmol) were added, and the solution stirred 3 h while warming to r.t. The reaction was concentrated in vacuo and purified by silica gel chromatography (8% MeOH/CHCl3) to give 1.42 g (74%) of 2-amino-N-methyl-3-nitro-benzamide as a yellow solid. 1H NMR (300 MHz, DMSO-d6) δ 8.58 (br s, 1H), 8.23 (br s, 2H), 8.15 (dd, 1H, J=8.1, 1.8 Hz), 7.82 (dd, 1H, J=8.1, 1.8 Hz), 6.68 (t, 1H, J=8.1 Hz), 2.76 (d, 3H, J=4.5 Hz). 2,3-Diamino-N-methyl-benzamide. 2-Amino-N-methyl-3-nitro-benzamide (1.4 g, 7.2 mmol) was reduced by hydrogenation using 50 psi of H2 with 10% Pd—C, (250 mg) in EtOAc (25 mL) for 5 h. After filtering through Celite, solvent was removed in vacuo. Purification by silica gel chromatography (10% MeOH/CHCl3) gave 1.08 mg (91%) of 2,3-diamino-N-methyl-benzamide as a faintly yellow solid. 1H NMR (300 MHz, CDCl3) δ6.87 (dd, 1H, J=7.8, 1.5 Hz), 6.76 (dd, 1H, J=7.8, 1.5 Hz), 6.59 (t, 1H, J=7.8 Hz), 6.14 (br s, 1H), 4.28 (br s, 4H), 2.95 (d, 3H, J=5.1 Hz).

Provenance & Evidence