Hydroxyamine hydrochloride → 1-(2-Fluorophenyl)-2-(1,1,1-trifluorobut-3-en-2-yloxy)ethanone oxime

Participants

Reaction Conditions

Reaction Steps

To a reactor was added hydroxylamine hydrochloride (0.34 kg, 4.95 mol), sodium acetate (0.47 kg, 5.70 mol) and MeOH (2.68 L). To this suspension was charged a solution of 1-(2-fluorophenyl)-2-(1,1,1-trifluorobut-3-en-2-yloxy)ethanone (0.998 kg, 3.806 mol) in MeOH (1.8 L) and the reaction mixture was heated to 40-50° C. Upon completion (ca. 2 h) the reaction mixture was cooled to rt, and filtered over Celite (0.5 wt) and rinsed with EtOAc (3.0 L). The filtrate was concentrated under vacuum and to the resulting residue was added methyl tert-butyl ether (6.3 L), water (0.94 L) and sat. aq. NaHCO3 (2.5 L). The organic phase was washed once with water (1.6 L) and sat. aq. NaCl (0.1 L). The organic phase was concentrated under vacuum to afford the title compound as an oil (1.03 kg, 95.0%). 1H NMR (500 MHz, CDCl3) δ ppm 7.49-7.35 (m, 2H), 7.24-7.06 (m, 2H), 5.78-5.65 (m, 1H), 5.54-5.40 (m, 2H), 4.89-4.81 (m, 1H), 4.53 (d, J=12.6 Hz, 1H), 4.47 (d, J=12.6 Hz, 0.5H), 4.27-4.18 (m, 1H), 4.13-4.05 (m, 0.5H).

Provenance & Evidence