5-Ethyl-2-Furoic Acid

Abstract

Ethyl 5-Ethyl-2-furoate. A mixture of 50.6 g (0.25 mole) of ethyl 5-(1-chloroethyl)-2-furoate (see p. 76), b.p. 108–1100/0.5 mm, and 150 ml of glacial acetic acid was prepared in a 500-ml four-necked round-bottomed flask fitted with mercury-sealed stirrer, reflux condenser carrying a gas-outlet tube, thermometer, and glass tube passing to the bottom of the flask and serving for the introduction of hydrogen chloride. Over a period of 20–30 minutes, 49 g (0.75 g-atom) of zinc dust was added in small portions to the vigorously stirred mixture (Note 1). When all of the zinc had been added, a stream of dry hydrogen chloride was passed into the mixture for 3.5–4 hours at such a rate that the temperature of the mixture did not rise above 55–60° (Note 3). When saturated with hydrogen chloride, the reaction mixture was heated in a water bath for 20–30 minutes (Note 4).