Phosphorus oxychloride → HCID 86672829, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 1-(4-fluorophenyl)-1H-pyrazolo[3,4-d]pyridazin-4-ol (1.30 g, 5.65 mmol), and POCl3 (25 mL) is warmed at 100° C. After 4 hours, the reaction mixture is cooled to room temperature and added dropwise to ice cold water, followed by periodic addition of crushed ice to control the exotherm. To the aqueous solution is added EtOAc and the mixture is neutralized with sodium bicarbonate. The organic layer is separated and the aqueous layer is extracted with EtOAc (3×50 mL). The combined organic layers are washed with saturated aqueous sodium bicarbonate (2×30 mL) and brine (2×30 mL), dried over magnesium sulfate, filtered and concentrated to afford 4-chloro-1-(4-fluorophenyl)-1H-pyrazolo[3,4-d]pyridazine, which is used without purification.

Provenance & Evidence