Phosphorus oxychloride → 2-(6-Chloro-3-pyridazinyl)phenol

Participants

Reaction Steps

Dimethylformamide (85 ml.) was cooled to 5° and phosphorus oxychloride (115 ml.) was added slowly to maintain a solution temperature below 60°. 6-(2-Hydroxyphenyl)-3(2H)-pyridazinone (30 g., 0.16 m.) was added rapidly in several portions. The reaction mixture was heated to 85° and held at this temperature for 4.5 hours with stirring. The mixture was then cooled to 35° and poured into 1 liter of ice cold water keeping the quenched solution below 35°. The resulting precipitate was filtered off, washed with water and dried to give 30.8 g. (96% yield) of crude 3-chloro-6-(2-hydroxyphenyl)pyridazine.

Provenance & Evidence