1-bromo-4-(3,3,3-trifluoroprop-1-en-2-yl)benzene

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Osmium tetroxide (4 wt % solution with water, 4.3 mL, 0.70 mmol) was added to a stirring mixture of 1-bromo-4-(1-(trifluoromethyl)ethenyl)benzene (3.5 g, 14 mmol), 4-methylmorpholine N-oxide (1.8 g, 15 mmol), acetone (14 mL), and water (14 mL) at room temperature. After 21 h, Na2SO3 (8.8 g, 70 mmol) was added, the mixture was filtered. Silica gel (20 g) was added to the filtrate, and the volatiles were removed in vacuo. The residue was purified via column chromatography (5% MeOH in CH2Cl2) to afford 2-(4-bromophenyl)-3,3,3-trifluoro-1,2-propanediol (3.0 g) as an off-white solid. the mixture was filtered Silica gel (20 g) was added to the filtrate the volatiles were removed in vacuo The residue was purified via column chromatography (5% MeOH in CH2Cl2)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: n-BuLi (9.5 mL, 2.5 M solution with toluene, 24 mmol) was added to a stirring mixture of methyltriphenylphosphonium bromide (8.5 g, 24 mmol) and THF (100 mL) at room temperature under a nitrogen atmosphere. After 1 h, 1-(4-bromophenyl)-2,2,2-trifluoroethanone (3.0 mL, 20 mmol, Sigma-Aldrich, St. Louis, Mo.) was added. After an additional 1 h, saturated aqueous ammonium chloride (50 mL) was added. The mixture was partitioned between diethyl ether (100 mL) and saturated aqueous ammonium chloride (50 mL). The layers were separated, the organic material was washed sequentially with saturated aqueous ammonium chloride (50 mL) and brine (50 mL), dried (MgSO4), and purified via column chromatography (35 g of silica, 1% EtOAc in hexanes) to provide 1-bromo-4-(1-(trifluoromethyl)ethenyl)benzene (3.5 g) as an orange oil. After an additional 1 h The mixture was partitioned between diethyl ether (100 mL) and saturated aqueous ammonium chloride (50 mL) The layers were separated the organic material was washed sequentially with saturated aqueous ammonium chloride (50 mL) and brine (50 mL) dried (MgSO4) purified via column chromatography (35 g of silica, 1% EtOAc in hexanes)