Phosphorus oxychloride → 3-Chloro-5-(trifluoromethyl)pyridazine

Participants

Reaction Conditions

Reaction Steps

5-(Trifluoromethyl)pyridazin-3(2H)-one (20.0 g, 111 mmol) was dissolved in 1,4-dioxane (222 mL) and POCl3 (31.0 mL, 333 mmol) added. The reaction was left to stir at 80° C. for 3 h. After consumption of the starting material, the reaction was cooled to room temperature. The reaction mixture was added to ice and quenched with ammonium hydroxide. The aqueous layer was extracted with dichloromethane (×3) and the organic layers combined, dried with magnesium sulfate, filtered, and concentrated under reduced pressure. The residue was purified by flash chromatography to afford the title compound as an orange oil. 1H NMR (500 MHz, CDCl3) δ 9.37 (s, 1H); 7.76 (s, 1H).

Provenance & Evidence