Ethanol → 3-Fluoro-N-hydroxy-4-methylbenzamidine

Participants

Reaction Steps

To a suitable vessel equipped with mechanical stirrer under N2 atmosphere was charged 202.0 g of 3-fluoro-4-methylbenzonitrile followed by 1.0 L of ethanol. Hydroxylamine (144 mL of 50% solution in water) was added via addition funnel over 20 minutes. The mixture was stirred at ambient temperature until HPLC analysis showed that reaction was complete (no starting material remained). Water (3.0 L) was added dropwise to the pale yellow solution over 1 hour to give a thick slurry. The slurry was cooled in an ice water bath to 2° C. for 1.5 hours, filtered and dried under vacuum at 35° C. for 22 hours to give the title compound (230.3 g, 91.6%) as a white solid. 1H-NMR (CDCl3, 500 MHz) δ 7.30 (m, 2H), 7.19 (m, 1H), 4.87 (s, 2H), 2.28 (s, 3H); 13C-NMR (CDCl3, 500 MHz) δ162.15, 160.19, 151.58, 131.82, 131.76, 131.66, 131.62, 127.01, 126.87, 121.06, 112.69, 112.51, 14.48; 19F-NMR (CDCl3, 500 MHz) δ-116.35, −116.37, −116.39. LC-MS M+H169.19,

Provenance & Evidence