Hydrochloric Acid → 2-(2-Chloroethoxy)-1-(6-fluorobenzo[b]thiophen-5-yl)ethanol

Participants

Reaction Steps

To a solution of 1.6 g of 6-fluorobenzo[b]thiophene-5-carbaldehyde in 30 ml of tetrahydrofuran is dropwise added 10 ml of 1.6M tetrahydrofuran solution of 2-chloroethoxymethylmagnesium chloride at -30° C. over ten minutes, and thereafter, the resulting mixture is stirred while ice-cooling for one hour. Subsequently, the thus stirred reaction mixture is introduced into a mixture of 50 ml of ice water, 50 ml of ethyl acetate and 2 g of ammonium chloride, and the resulting mixture is adjusted to pH 2 with 6N hydrochloric acid. Thereafter, the thus pH-adjusted mixture is stirred at the same temperature for five minutes. Subsequently, the thus stirred reaction mixture is adjusted to pH 6 with a saturated aqueous sodium hydrogencarbonate solution. Thereafter, the resulting organic layer is separated, washed successively with water and a saturated saline solution, and then dried over anhydrous magnesium sulfate. The solvent is then removed from the thus dried layer by distillation under reduced pressure. The residue obtained is purified by a column chromatography [eluent: toluene:ethyl acetate=4:1], to obtain 1.3 g of oily 2-(2-chloroethoxy)-1-(6-fluorobenzo[b]thiophen-5-yl)ethanol.

Provenance & Evidence