Isatoic Anhydride → 2-Amino-N-methoxybenzamide

Participants

Reaction Steps

O-Methylhydroxylamine hydrochloride (1.253 g, 15.00 mmol) was added to 1H-3,1-benzoxazine-2,4-dione (isatoic anhydride) (1.631 g, 10 mmol) in THF (50 mL) containing DIPEA (2.79 ml, 16.00 mmol). The resulting solution was stirred at room temperature for 4 hours and then heated to reflux for 17 hours. The mixture was allowed to cool to room temperature, filtered and then evaporated. The residue was dissolved in MeOH (20 mL) and then loaded onto an SCX column. The mixture was eluted first with MeOH and then with a 7N solution of NH3 in MeOH. Fractions containing product were combined and then evaporated to afford 2-amino-N-methoxybenzamide (1.410 g, 85% yield); 1H NMR spectrum: (300 MHz, DMSO) δ 3.67 (3H, s), 6.26 (2H, s), 6.48 (1H, m), 6.70 (1H, dd), 7.15 (1H, m), 7.31 (1H, dd), 11.36 (1H, s); Mass spectrum: m/z (ESI+) (M+H)+=167.41.

Provenance & Evidence