反应详情

A Grignard reagent is prepared from 25.0 g (0.146 mol) of 2-bromotoluene and 4.3 g (0.175 mol) of magnesium in 100 ml of diethyl ether. The Grignard reagent is added dropwise to a solution of 22.8 g (0.161 mol) ethyl trifluoroacetate in 120 ml of diethyl ether at −78° C. The reaction mixture is allowed to warm to room temperature and stirred for one additional hour. 300 ml of NH4Cl aq and 100 ml of 1N HCl are then added to the mixture. The aqueous phase is removed, the organic phase is washed with NH4Cl aq and brine, dried over MgSO4, and concentrated. The residue is purified by flash chromatography on silica gel with hexane as an eluent, yielding 6.3 g of 2,2,2-trifluoro-1-(2-methylphenyl)-ethanone as colorless liquid.

1. customThe aqueous phase is removed
2. washthe organic phase is washed with NH4Cl aq and brine
3. dry with materialdried over MgSO4
4. concentrationconcentrated
5. customThe residue is purified by flash chromatography on silica gel with hexane as an eluent