Boron tribromide → 5-Amino-1-(4-fluorophenyl)4-[3-hydroxybenzoyl]pyrazole

Participants

Reaction Steps

To an ice-cooled solution of 5-amino-1-(4-fluorophenyl)-4-(3-methoxybenzoyl)-pyrazole (3.0 g, 10.0 mmol) in methylene chloride (25 ml) was added boron tribromide (51 ml, 51 mmol, 1 M solution in methylene chloride). After 1 h, the reaction mixture was poured into brine and the product was extracted into ethyl acetate. The organic layer was dried over sodium sulfate, filtered and concentrated in vacuo to give 5-amino-1-(4-fluorophenyl)-4-[3-hydroxybenzoyl]pyrazole (2.4 g).

Provenance & Evidence