Hydrochloric Acid → HCID 22666364, compound

Participants

Reaction Conditions

Reaction Steps

In 66 mL of dimethyl sulfoxide is dissolved 15.2 g of ethyl 4-ethoxycarbonyl-2,3,6-trifluorophenylacetate, to which are added 7.84 g of potassium carbonate and 4.54 g of sodium hydrosulfide n-hydrate(purity 70%). The mixture is stirred at 40° C. for 2 hours. The reaction mixture is cooled to 5° C., 8.1 mL of tert-butyl chloroacetate is added, and the mixture thus formed is stirred at the same temperature as above for 20 minutes. Then, 6.36 g of potassium tert-butoxide is added and stirred for one hour. Water and ethyl acetate are added to the reaction mixture, pH is adjusted to 1 with 6 mol/L hydrochloric acid, and the organic layer is separated. The organic layer is washed with water, saturated aqueous solution of sodium bicarbonate and saturated aqueous solution of sodium chloride successively and dried over anhydrous magnesium sulfate, and the solvent is distilled off under reduced pressure. Thus, 19.2 g of tert-butyl 6-(2-ethoxy-2-oxoethyl)-5,7-difluoro-3-oxo-2,3-dihydrobenzo[b]thiophene-2-carboxylate is obtained.

Provenance & Evidence