GB536806A - Preparation of esters of ª‡-chloracrylic acid - Google Patents

Abstract

536,806. Esters of α-chloracrylic acid. CLEVELAND, F. J. (Pittsburgh Plate Glass Co.) Aug. 22, 1939, No. 24209. [Class 2 (iii)] Esters of α-chloracrylic acid are prepared by dehydrochlorinating the corresponding ester of α, or α# dichloropropionic acid by treatment with an alkaline reagent in an amount not substantially in excess of the amount theoretically required to combine with the chlorine and hydrogen radicles to be eliminated, whereby saponification of the ester is avoided. The temperature of dehydrochlorination is preferably maintained below room temperature. The alkyl esters such as ethyl, propyl, butyl, amyl, n-hexyl, octyl, laural and octadecyl esters, other aliphatic esters including ally], oleyl and cyclohexenyl esters, polyhydric alcohol esters including the esters of ethylene or propylene glycol, glycerine, mannitol and hexamethylene glycol, and aryl, aralkyl, cycloparaffinic and heterocylic esters including phenyl, cresyl. resorcinyl, naphthyl, benzyl, phenylethyl, cyclohexyl, fenchyl, chlolesteryl, furfural and thienyl esters, may be prepared. The preparation may be carried out by adding an alcoholic solution of potassium or sodium hydroxide to the dichloro ester, filtering and distilling under reduced pressure, if desired in the presence of a polymerization inhibitor. In an example, an aqueous slurry containing sodium carbonate is added to methyl α#-dichloropropionate containing hydroquinone, the temperature being maintained at 10‹-12‹C. with agitation, the reaction mixture being filtered and distilled. The esters produced polymerize more easily than the corresponding acrylic or methacrylic esters to give highly transparent products.