114 W. A. Drushel — Preparation and Hydrolysis of 



suitable for the preparation of the ester in sufficiently pure 

 condition to study its properties and rate of hydrolysis. 



(c) Method of Blaise and Maire.* Blaise and Maire passed 

 into glacial acetic acid at 0° the formaldehyde vapor obtained 

 by the depolymerization of trioxymethylene. The saturated 

 acetic acid solution was then allowed to warm up slowly, 

 resulting in a polymer of formaldehyde less complex than 

 trioxymethylene. This polymer was condensed with bromacetic 

 ester in the presence of zinc in a mixture of equal parts of 

 absolute alcohol and ethyl acetate. They obtained a 40 per 

 cent yield of ethyl hydracrylate whose boiling point was given 

 as 81° at 13 mm pressure. It is to be observed that this boiling 

 point is about the same as that given for Curtius and Miiller's 

 admittedly impure ethyl hydracrylate. 



(d) Direct Esterification Method. In view of the instability 

 of beta-oxyacids on heating in the presence of mineral acids, 

 and of the work of Bogojawlensky and .Narbutf on the use of 

 anhydrous copper sulphate to facilitate esterification in the 

 presence of acid catalyzers, and the more recent work of Clem- 

 mensen and Heitman:): on the use of anhydrous copper sulphate 

 in the esterification of certain oxyacids in the absence of any 

 catalyzing acid, it seemed reasonable to expect this procedure 

 to be applicable for the preparation of pure ethyl hydracrylate. 

 The work of preparing ethyl hydracrylate resolved itself into 

 two parts, 1st, the preparation of a sufficiently large amount of 

 pure hydracrylic acid, and 2d, the esterification of the acid. 



1. The preparation of hydrac? 7 ylic acid. — Of the several 

 methods described for the preparation of hydracrylic acid the 

 method using glycerine as a starting-out material, with certain 

 modifications, was found to be the most expedient for prepar- 

 ing the pure acid in considerable quantity. The modifications 

 of former methods which will be pointed out resulted in 

 increasing the yield and purity of the hydracrylic acid. 



A kilo of glycerine was mixed with a liter of water and 

 oxidized in 200 cm3 portions by fuming nitric acid in tubes about 

 20 mm in internal diameter kept cold by running water, accord- 

 ing to the procedure outlined by Mulder.g After the oxida- 

 tion was complete the liquid was concentrated in 400 cm3 portions 

 on the steam bath to remove any dissolved nitrous acid. On 

 cooling some oxalic acid crystallized out. The filtrates from 

 the several 400 cm3 portions were combined and treated with a 

 little more than enough calcium carbonate to precipitate out 

 the dissolved oxalic acid as calcium oxalate, which was removed 

 by filtration. The filtrate was diluted with water to 3 liters 



* Blaise and Maire, C. r. d. l'Acad. des Sciences, cxlii, 215-17. 

 , f Bogojawlensky and Narbut, Ber. Dtsch. Chem. Gesellsch., xxxviii, 3344. 

 j Clemmensen and Heitman, Am. Chem. Jour., xl, 319. 

 § Mulder, Ber. Dtsch. Chem. Gesellsch., ix, 1902. 



