Cesium fluoride → 2-(Pyridazin-4-yl)-4-(trifluoromethyl)phenol

Participants

Reaction Conditions

Reaction Steps

To a 5 L jacketed vessel was added acetonitrile (9 L) and the solvent was sparged with nitrogen for 2 hours. To the solvent was added cesium fluoride (335.8 g, 2.21 moles), 4-(tributylstannyl)pyridazine (408 g, 1.11 moles), 4-trifluoromethyl-6-iodophenol (318.33 g, 1.11 moles), palladium tetrakis triphenylphosphine (61.31 g, 53.05 mmole) and copper (I) iodide (40 g, 210 mmol) at 20° C. The resulting orange suspension was heated to 45-50° C. for 2 hours. The reaction was cooled and partitioned between ter-tbutylmethylether (2×5 L) and 2N (aq) HCl (2×5 L). The resulting biphasic solution was filtered and the layers separated. The aqueous phases were combined and basified with 4M (aq) sodium hydroxide solution (6 L) to obtain a pH=4-5. The resulting suspension was extracted into ethyl acetate (10 L) and the organic layer concentrated to dryness to afford the title compound (204 g, 60%) as an orange solid.

Provenance & Evidence