Methyl 5-(Chloromethyl)-2-Furoate

Abstract

A mixture of 126 g (1 mole) of methyl 2-furoate (see p. 27), b.p. 180–181°/760 mm, 250 ml of dry dichloroethane (Note 1), 45 g of paraformaldehyde (1.5 moles calculated as formaldehyde), and 34 g (0.25 mole) of anhydrous zinc chloride was prepared in a one-liter four-necked round-bottomed flask fitted with stirrer, bent tube reaching to the bottom of the flask, thermometer, and gas-outlet tube. A rapid stream of hydrogen chloride was passed first through a wash bottle containing sulfuric acid and then into the stirred mixture. The temperature of the reaction mixture gradually rose; in order to avoid resinification, the flask was cooled with water so as to prevent the temperature from rising above 24–26°. The reaction lasted about two hours; the end of the reaction was indicated by the complete dissolution of the para-formaldehyde: the spontaneous evolution of heat gradually stopped, and the mixture became light yellow in color.