ACETO ACETIC ESTER 12} 



cold with ammonia forms a compound C IO H X 8 N 2 O 4 , if moisture be 

 excluded. It is represented thus : 



CH, 



NH 2 

 ONH 4 



/ \ 

 C0 2 RC CH 



I I 

 CH 3 C C < 



\ / 

 O 



Isodehydracetic ester can be prepared from sodacetoacetic ester and 

 /3-chlorcrotonic ester which proves its constitution thus : 



C0 2 C 2 H 5 CH 3 CO 2 C 2 H 5 CH 



CH 3 CO C 



C : CH CH 3 C : C C : CH. 



C: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, CH 3 C(SC 6 H 5 ) 2 CH 2 CO 2 C 2 H 5 , 

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

 butyric ester, CH 3 C (SO 2 C 6 H 5 ) 2 CH 2 CO 2 C 2 H 5 , is obtained, it melts 

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

 water. -Ethyl-/9-diethylsulfonebutyric ester, CH 3 C (SO 2 C 2 H 5 ) 2 CH 

 (C 2 H 5 ) CO 2 C 2 H 5 , formed in a similar manner from the condensation 

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

 87-88 a-Methyl-/9-diethylsulfonebutyric ester melts at 79? a-Ethyl- 

 /9-dithiophenylbutyric ester, CH 3 C (SC 6 H 5 ) 2 CH (C 2 H 5 ) CO 2 C 2 H 5 , 

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

 and melts at jo- r ji From this by the above method was prepared 

 tt-ethyl-^-diphenylsulfonebutyric ester, CH 3 C(SO 2 C 6 H 5 ) 2 CH(C 2 H 5 ) 

 CO 2 C 2 H 5 , which melts at ui. 



