Carbon tetrabromide → HCID 57941503, compound

Participants

Reaction Conditions

Reaction Steps

Triphenylphosphine (0.54 g, 2.1 mmol) was added to a solution of (3-trifluoromethyl-1-trityl-1H-pyrazol-4-yl)-methanol (0.6 g, 1.5 mmol) in dichloromethane (25 mL). The resulting solution was cooled to −20° C. and a solution of carbon tetrabromide (0.54 g, 1.6 mmol) in dichloromethane (5 mL) was added in four portions. The solution was stirred for 5 min at −20° C. and then at for 3 h at 0° C. Further portions of triphenylphosphine (0.17 g, 0.65 mmol) and carbon tetrabromide (0.24 g, 0.72 mmol) were added. The solution was stirred for 3 h, and further portions of triphenylphosphine (0.54 g, 2 mmol) and carbon tetrabromide were added. The solution was stirred for 30 min and then the solvent was evaporated and the residue purified by flash chromatography, eluting with 5-10% ethyl acetate/petroleum ether to give 4-bromomethyl-3-trifluoromethyl-1-trityl-1H-pyrazole (0.30 g, 43%) as a white solid.

Provenance & Evidence