Azobisisobutyronitrile → Diethyl (2-bromo-4-(bromomethyl)phenyl)(difluoro)methylphosphonate

Participants

Reaction Steps

A solution of [(2-bromo-4-methyl-phenyl)-difluoro-methyl]-phosphonic acid diethyl ester (10.93 g, 30.6 mmol), N-bromosuccinimide (5.45 g, 30.6 mmol) and AIBN (100 mg) in benzene (300 mL) was refluxed for 18 h. The reaction mixture was concentrated in vacuo and redissolved in Ethyl acetate (200 mL). The solution was washed with H2O (50 mL), HCl (1 N, 50 mL), NaHCO3 (5%, 50 mL) and H2O (50 mL). The solvent was removed and the residue was purified by column chromatography on silica gel, eluting with hexanes/EtOAc (4:1) to provide a colorless oil (9.6 g, 80% purity with starting material as byproduct), which was taken on to the next step without further purification.

Provenance & Evidence