Acetic Anhydride → 4-(4-Chloro-2-methoxyphenyl)pyridin-2(1H)-one

Participants

Reaction Conditions

Reaction Steps

4-(4-Chloro-2-methoxyphenyl)pyridine 1-oxide (673 mg, 2.86 mmol) and acetic anhydride (10 mL) were heated at reflux for 3 h. The mixture was concentrated under reduced pressure, and a 1:1 solution of H2O/MeOH (20 mL) was added. The reaction mixture was heated to reflux for 1 h, cooled to 25° C. and concentrated under reduced pressure. The resulting residue was dissolved in hot 2-propanol (3 mL), triturated with Et2O, sonicated for 30 min then placed in the freezer. The solid was filtered off providing the title compound (550 mg, 91%) as a tan solid: 1H NMR (500 MHz, DMSO-d6) δ 11.54 (s, 1H), 7.35-7.33 (m, 2H), 7.01 (s, 1H), 7.08 (d, J=6.6 Hz, 1H), 6.36 (s, 1H), 6.28 (s, 1H), 3.82 (s, 3H); ESI MS m/z 235 [M+H]+.

Provenance & Evidence