Phosphorus oxychloride → N-[3-(6-chloro-3-pyridazinyl)phenyl]propanamide

Participants

Reaction Steps

To a refluxing solution of 0.63 g of N-[3-(1,6-dihydro-6-oxo-3-pyridazinyl)phenyl]propanamide in 100 ml of dry tetrahydrofuran was added 0.5 ml of phosphorus oxychloride. After 1.5 hours, 0.5 ml of phosphorus oxychloride was added and after 2 hours of refluxing 0.25 ml of phosphorus oxychloride was added. The solution was refluxed for an additional hour, then the solvent was removed, dichloromethane was added and the solution was poured into ice water. The mixture was neutralized with sodium bicarbonate and extracted with dichloromethane. The extracts were combined, washed with water, dried and the solvent removed giving an oil. This oil was chromatographed on thick layer silica gel preparative plates with dichloromethane:methanol (95:5), as solvent to give 0.33 g of solid. Recrystallization of 0.15 g from dichloromethane-acetone-hexane gave the desired compound as white crystals, mp 188°-189° C.

Provenance & Evidence