ACETO ACETIC ESTER 



123 



cold with ammonia forms a compound Cio Hjs N2 O4, if moisture be 

 excluded. It is represented thus : — 



CH3 



I 

 C 



/ \ 

 CO, RC CH 



CH3 C C < 



\ / 

 O 



NH2 

 ONH. 



Isodehydracetic ester can be prepared from sodacetoacetic ester and 

 /5-chlorcrotonic ester which proves its constitution thus : — 



CO2 C2 Hj CH3 



CH, CO— C 



H 



NaCl 



C:CH— CH,C:C 



C2H5O CO 



O 



AUTENRIETH, W., 1890. 



Ann. Chem 259, 365-373 ; J. Chem. Soc. 60, 204. 



Sulfur Derivatives of Acetoacetic, Methylacetoacetic and 

 Ethylacetoacetic Esters. 



By treating /9-dithiophenylbutyric ester, CH3C(SC6H5)2CH2C02C2H5, 

 with sulfuric acid and potassium permanganate, /9-diphenylsulfone- 

 butyric ester, CH3 C (SO2C6 H5)2 CH2CO2 C, H5 , is obtained, it melts 

 at 97°, is soluble in hot alcohol, ether and benzene and insoluble in 

 water. «-Kthyl-/9-diethylsulfonebutyric ester, CH3 C (SO2 C2 H5)2 CH 

 (C2 H5) CO2 C2 H5 , formed in a similar manner from the condensation 

 product of ethyl mercaptan and ethyl-acetoacetic ester, melts at 

 87°-88.° a-Methyl-/?-diethylsulfonebutyric ester melts at 79.° a-Ethyl- 

 /9-dithiophenylbutyric ester, CH3 C (SC5 H5)2 CH (C2 H5) CO2 C2 H5 , 

 is made by condensing ethyl-acetoacetic ester and phenyl mercaptan, 

 and melts at ']o°-']i° From this by the above method was prepared 

 «-ethyl-/3-diphenylsulfonebutyric ester, CH3C(S02C6H5)2CH(C2H5) 

 CO2C2H5, which melts at iii.° 



