Potassium Phosphate, Tribasic → 5-Amino-1-(4-fluorophenyl)-4-[3-(pyridin-3-yl)benzoyl]pyrazole

Participants

Reaction Conditions

Reaction Steps

A mixture of 5-amino-4-(3-bromobenzoyl)-1-(4-fluorophenyl)pyrazole (0.9 g, 2.5 mmol) [prepared as described in Example 1 above], pyridine-3-boronic acid, 1,3-propanediol cyclic ester (0.5 g, 3 mmol), potassium phosphate (0.8 g, 3.73 mmol) and tetrakistriphosphine palladium (0.3 g, 0.25 mmol) in dioxane (20 ml) was heated at 85° C. under argon. After 16 h, the reaction mixture was cooled to room temperature and poured into brine. The product was extracted into ethyl acetate, dried over sodium sulfate and filtered. The organic layer was removed in vacuo and the residue was purified by flash chromatography (elution gradient: 40-80% ethyl acetate/hexane) to give 5-amino-1-(4-fluorophenyl)-4-[3-(pyridin-3-yl)benzoyl]pyrazole (0.50 g) which was recrystallized from ethyl acetate (mpt. 222.2-223.0).

Provenance & Evidence