W. A. Drushel — Substituted Aliphatic Acids. 517 



esters for decinormal hydrochloric acid at 25° to the velocity 

 constants of the corresponding unsubstituted esters. 



From the results obtained it appears that the presence of the 

 cyanogen group in the acid radical has in general a very 

 marked retarding influence upon the velocity of the hydrolysis 

 of the esters of such acids. In this respect cyanogen behaves 

 like halogen, but the retarding effect of cyanogen, unlike that 

 of the halogens, is more marked when the cyanogen has the 

 alpha position than when it has the beta position. This in- 

 fluence of position was observed in both the cyanogen sub- 

 stituted propionates and the cyanogen substituted butyrates. 



At the temperatures and acid concentration used in this 

 series of experiments no hydrolysis of the cyanogen group was 

 observed. 









Table 



I. 







Hydroly 



sis at 25° 









N/10 HC1 







Ethyl 



cyan- 



Ethyl cyan- 



Ethyl a- 



Ethyl a- 



Ethyl a- 



Ester 



propionate 



butyrate 



cyan-va- 



cyan-iso- 



cyan-di- 





a 



P 



a )3 



lerianate 



valerianate 



ethylacetate 



Time 



14580 



12000 



14580 



19200 



19200 



14580 





9-90 



12-7 



6-31 



(6-88)* 



2-64 



2-68 





9-10 



12-0 



(5.47)* 



4-90 



(3-07)* 



2-90 



10 6 K 



9-17 



12-8 



6-25 



4-53 



2-58 



2-59 



9-06 



13-2 



6-12 



4'55 



2-31 



2-37 





9-16 



13-4 



6-32 



4-68 



2-25 



2-69 





8-60 



13-4 



6-19 



4-67 



2-72 



2-40 





8-90 



13-6 



6-38 











9-23 



13'3 











Average 



9-14 13-0 



6-15 



4-67 



2-50 



2-58 



Hydrolysis at 35° 



Time 



10 5 K 



Average 



6060 

 22-5 

 24-0 

 22-9 

 22-8 

 22-5 

 22*5 

 226 



6060 

 33-3 

 33-2 

 33-5 

 33-4 

 33-8 

 (28-7) ! 

 33-2 



13200 

 14-2 

 14-5 

 13-9 

 14-1 

 13-9 

 13-9 

 13-9 



6930 



20 

 20 



20 

 21 

 20 

 20 



20 



6930 



13-7 

 13-5 

 13-4 

 14-1 

 14-1 

 135 

 146 



22-7 33-4 14-1 20-4 13'9 



* Not included in the average. 



6930 

 6-76 

 6-55 

 6-32 

 6-46 

 6-30- 

 6-54 

 6-51 



6-49 



6930 

 (7'40)* 

 6-46 

 7-08 

 6-02 

 6-17 

 6-52 

 6-71 



6-53 



