Drushel and Holden — Rydr acrylic Esters. 



513 



for atmospheric pressure were estimated by the graphic method. 

 The results are recorded in Table II. 













Table 



II. 



















Boi 



ling points of hydracrylic esters. 









Methyl 



Ethyl 



Isopropyl 



Propyl 



Isobutyl 



Isoamyl 



ester 



ester 



ester 



ester 



ester 



ester 



A 





Press. 





Press. 





Press. 





Press. 





Press. 



Press. 





in 





in 





in 





in 





in 





in 



B.P. 



mm. 



B.P. 



mm. 



B.P. 



mm. 



B.P. 



mm. 



B.P. 



mm. 



B.P. 



mm. 



'79 



12 



84 



12 



95 



12 



98 



12 



104 



15 



121-5 



17 



87 



20 



91-5 



19 



99 



20 



102 



19 



112 



20 



124 



20 



107-5 



40 



955 



22 



109 



35 



120 



43 



126 



45 



137 



36 



111 



56 



116 



62 



114 



42 



127 



62 



129 



50 



147 



58 



121 



94 



127 



102 



128-5 



82 



142 



107 



143 



88 



159 



95 



184** 



760 



190** 



760 



196** 



760 



205** 760 



212** 



760 



225** 



760 













** Calculated. 













All of the esters of this series below the isobutyl ester are 

 freely soluble in water in all proportions, but the higher 

 homologues are not. The isobutyl ester is soluble in 18 parts 

 of water and the isoamyl ester in 60 parts of water at room 

 temperature. 



The refractive indices of the esters were determined by 

 means of the Pulfrich refractometer for the D line of sodium 

 light and the following results obtained : 



Table III. 



(n-1)- 



M 



M 



Methyl hydracrylate 1-4306 



Ethyl 



Propyl " 

 Isopropyl " 

 Isobutyl " 

 Isoamyl " 



40-10 104-0 



" 1-4271 47-30 118-0 



" 1-4341 54-85 132-0 



" 1-4303 53-68 132-0 



" 1-4342 63-70 146*0 



" 1-4374 71-65 160-0 



These indices of refraction were determined at 23° C. 



Conclnsio7is : — 



1. Hydracrylic acid is obtained from glycerine in a fair 

 yield by slight modifications of the methods described in the 

 literature. 



2. Removal of the iodine from sodium /3-iodopropiouate 

 rather than from the free acid by means of silver oxide has the 

 advantage that the reaction goes at room temperature and 

 requires only about half of the silver oxide theoretically 

 required when the free acid is used instead of the sodium salt. 

 Precautions must, however, be taken to prevent the solution 

 from becoming alkaline. This is important since on evaporat- 



Am. Jour. Sci. — Fourth Series, Vol. XL, No. 239.— November, 1915. 

 34 



