Triethylamine → 1,2,3-Trifluorobenzene

Participants

Reaction Conditions

Reaction Steps

1.27 g of 3,4,5-trifluorophenol and 870 mg of triethylamine were dissolved in 10 ml of methylene chloride, and the solution was stirred at −78° C. To the solution was added dropwise 5 ml of a methylene chloride solution of 2-(2-(trans-4-(trans-4-propylcyclohexyl)cyclohexyl)ethyl)-1,3-dithianilium triflate obtained above (3.8 g), and the to solution was further stirred for one hour. 6.24 ml of Et3N.3HF was then -added, and a methylene chloride solution of bromine (6.24 g) was further added dropwise. After stirring at −70° C. for one hour, the reaction solution was allowed to gradually warm up. It was poured into 100 ml of a cold 3N sodium hydroxide solution at 0° C. and extracted with methylene chloride (30 ml×3). The organic layer was washed with water, dried over anhydrous magnesium sulfate, and then concentrated under reduced pressure. The resulting yellow oily substance was isolated and purified by a silica gel column chromatography with heptane as a developing solvent to obtain 1.0 g of 1-(3-(trans-4-propylcyclohexyl)cyclohexyl)-1,1-difluoropropyleneoxy)-3,4,5-trifluorobenzene as colorless crystals. A transition point thereof is shown below.

Provenance & Evidence