W. A. Drushel — Ethyl Hydracrylate. 113 



Art. VI. — On the Preparation and Hydrolysis of Ethyl 

 Hydracrylate ; by W. A. Drushel. 



[Contributions from the Kent Chemical Laboratory of Yale Univ. — cclxiii.] 



Hydracrylic acid is a well-known substance and has been 

 prepared by several methods ; its esters, however, have received 

 but little attention. In Beilstein's Handbuch the ethyl ester 

 alone is mentioned in connection with Klimenko's attempt to 

 prepare paracrylic acid. Only three references are given to 

 the ethyl ester in Richter's Lexikon and of these but one deals 

 with the direct preparation of the ester. Apparently in no 

 former investigation has hydracrylic ester been prepared by 

 the esterification of hydracrylic acid, nor was the ester obtained 

 in pure condition by any of the methods described in the liter- 

 ature. It seemed desirable therefore to prepare, if possible, 

 hydracrylic ester by the direct esterification of hydracrylic acid 

 in order to obtain the ester in pure condition for the purpose 

 of determining its properties and supplying additional hydrol- 

 ysis data for the series of esters studied in this laboratory. 



Preparation of the Ester : (a) Method of Klimenko."* Kli- 

 menko obtained what he called paracrylic acid by repeatedly 

 evaporating hydracrylic acid with concentrated hydrochloric 

 acid. He then heated 3 grams of this acid with an excess of 

 absolute alcohol at 150° and obtained an ester which boiled at 

 185° to 190° and p which he believed to be ethyl hydracrylate. 

 Ethyl hydracrylate, however, decomposes below 185° when 

 heated at ordinary pressure. In attempting to repeat Kli- 

 menko's work the author was unable to prepare the so-called 

 paracrylic acid by the method described. Baeyerf did not 

 believe that Klimenko had succeeded in preparing paracrylic 

 acid, (C 3 H 4 2 ) 2 , but rather that Klimenko's acid was an unsatu- 

 rated dibasic acid of the formula C 6 H 8 4 . If Baeyer's obser- 

 vation was correct Klimenko's ester could not have been 

 hydracrylic ester. 



(b) Method of Curtius and Miiller.J These investigators 

 obtained impure ethyl hydracrylate by converting beta-chlor- 

 propionic ester into beta-aminopropionic ester hydrochloride 

 and treating this with nitrous acid. The ester contained a 

 little chlorpropionic ester as an impurity, from which it could 

 not be freed by fractionation. The crude ester which they 

 obtained boiled at 80° to 84° at 12 mm pressure, or at 170° to 

 175° under ordinary pressure. The method is obviously not 



* Klimenko, Eafalowicz, Jour. Russ. Chem. Soc., xxvi, 412. 



f Baeyer, Ber. Dtsch. Chem. Gesellsch., xviii, 680. 



X Curtius and Miiller, Ber. Dtsch. Chem. Gesellsch., xlx, 850 ; xxxvii, 1276. 



A.M. Jour. Sci.— Fourth Series, Vol. XXXIX, No. 229.— January, 1915. 



