Phosphorus tribromide → 2,4-Dichlorophenethyl bromide

Participants

Reaction Conditions

Reaction Steps

2,4-Dichlorophenethyl alcohol (10 g, 52.0 mmol) was dissolved in 100 mL of methylene chloride, cooled to 0° C. under nitrogen atmosphere and 1.5 equiv of phosphorous tribromide (1M in CH2Cl2, 80 mmol, 80 mL) was added dropwise. The resulting reaction mixture was warmed to 23° C. and stirred for 2 h before the very slow addition of 200 mL of saturated aqueous sodium bicarbonate and extraction with methylene chloride (2×150 mL). The combined organic layers were dried over sodium sulfate and evaporated under reduced pressure. The crude product was purified by a SiO2 plug (5% EtOAc/hexanes) to yield 2,4-dichlorophenethyl bromide. The product was characterized by 1H NMR and HPLC.

Provenance & Evidence