ACETO ACETIC ESTER . 1 33 



WALDEN, P., 1891. 



Ber. 24, 2025-2039; J. Chem. Soc. 60, 1187. 



Tetric and Oxytetric Acids and their Homologues. 



Experiments were performed attempting to determine whether tetric 

 acid and its honiologues contain the carboxylic group but no definite 

 conclusions were reached. Oxytetric acid and its homologues were 

 shown to be alkyl substituted fumaric acids, thus oxytetric is mesaconic 

 or methyl fumaric, oxypentic is ethyl fumaric. etc. The acids described 

 by Demarcay as hydroxy tetric, etc., are identical with alkyl succinic 

 acids, hydroxytetric is methyl succinic and hydroxypentic is ethyl 

 succinic, etc. The acids are all obtained from the bromated alkyl aceto- 

 acetic esters. 



SPRAQUE, CHARLES T., 1891. 



J. Chem. Soc. 59. 329-343. 

 Thiacetoacetic Ester. 



This substance was produced and after carefully determining the 



melting point it was found to be between 75° and 78.° By the action of 



phenylhydrazin four bodies were produced : — (i) thiophenyl-methyl- 



pyrazolone ; (2) Knorr's phenylmethyl-pyrazolone-azobenzene ; (3) a 



substance, Cio Hg* N2 SO; (4) Knorr's bisphenyl-methyl-pyrazolone. 



The first one is 



NC6 H5 NCe H5 



y\ I \ 



N CO OC N 



II I I II 



CH3 C-CH-S-HC CCH3 



it is a weak base, dissolves in alkalis and weak acids reprecipitate it. 

 If it be heated with phenylhydrazin the other three above mentioned 

 compounds are produced. To the third product the author gave the 

 formula Cio Hg* N2 SO, but states that Holtzcka has since proven it to 

 be bisulphid of phenylmethyl pyrazolone (Cio H9 N2 0)2 S2. A method 

 was given for preparing a good yield of each one of the four products. 



* A disagreement, Cio Hs N2 SO is probably correct 



