QO The Philippine Journal of Science x9u 



place more readily when the 1, 4 hydrogen atoms are in a posi- 

 tion to most influence the =C0 groups. 



The absorption band of ethylsuccinosuccinate heading at 

 1/A=2,660 is shifted to 1/A=2,400 in the presence of sodium 

 ethoxide. This shift in position is entirely analogous to the 

 shift in the band of methylsalicylate and argues for a similar 

 structure.'" It has been shown that in methylsalicylate ^° and 

 some related compounds the influence of the carboxyl upon the 

 hydroxyl group is very marked and that the -^CO group of the 

 carboxyl is so affected by the neighboring hydroxyl that, in 

 certain respects, the ester behaves more like an ether. 



Acetylmethylsalicylate. — This compound was produced in a 

 manner analogous to that employed by Freer -' for the produc- 

 tion of the ethyl derivative; namely, by boiling methylsalicylate 

 with an excess of acetyl chloride. The yield seemed to be in- 

 creased by the presence of a small quantity of pyridine. The 

 ethyl ester boils at 272°, while we have found that the methyl 

 derivative boils at about 265^ with decomposition. Final puri- 

 fication was effected by distilling. A distillate with a constant 

 boiling point at 7 millimeters pressure of 122° was obtained. 

 This product was colorless, odorless, and produced only the 

 faintest coloration with ferric chloride solution. 



SUMMARY 



The absorption spectra of ethylsuccinosuccinate in neutral 

 and alkaline alcohol solutions, the diacetate in neutral solution, 

 the diimide in neutral and acid solutions, and acetylmethylsali- 

 cylate, have been measured. 



As a result of this work we believe that ethylsuccinosuccinate 

 exists in two forms, the enol and keto, which have different 

 melting points: 



COOEt H COOEt 



H2|'^^-0H H2|^N=0 



H0-'^Jh2 0=\Je2 



I /\ 



COOEt H COOEt 



Ai-< enol. Keto. 



"Gibbs and Pratt, This Journal, Sec. A (1913), 8, 44. 

 "Gibbs, Williams, and Galajikian, This Journal, Sec. A (1913), 8, 1; 

 and Gibbs and Pratt, loc. cit. 



"Joum. f. pr. Chemie (1893), 47, 246. 



