ACETO ACETIC ESTER 27 



DEMARCAY, E., 1880. 



Bull. Soc. chim. 33, 516-525 and 575-580 and 34, 31-37 ; J. Chem. 



Soc. 38, 625. 



Tetric and Oxytetric Acids and their Homologues. 



Methyl-acetoacetic ester when treated with bromin forms two com- 

 pounds, CH3 CO C (CH3) Br CO2 C2 H5 and CH^ Br CO C (CH3) 

 Br CO2 C2 H5. If these are allowed to stand they form CH3 CO C 

 (CH3) Br H and CH^ Br CO C (CH3) Br H, but if treated with 

 alcoholic potash they form tetric, 3 C4 H4 O2 + H2 O, and oxytetric acids, 

 3 C4 H4 O3+H2 O. Three sets of salts of tetric acid are formed, (i) 

 Cu O, C4 H4 O2 ; (2) Ba O, 2 C4 H4 O^ ; (3) 2 M^ O, 5 C4 H4 O^. 

 Phosphoric pentachlorid with tetric acid forms C4 H4 OCU which when 

 treated with chlorin gives C4 H4 CI4 O. 



In the above manner, from the alkyl substituted acetoacetic esters, 

 the following acids and many of their salts were produced ; pentic, 3 

 C5 H6 O2 + H2 O ; hexic, 3 Cs Hg O^ + H^ O ; heptic, 3 Cy H,o O^ + H^ 

 O ; oxypentic, 3 C5 Hg O3-I-H2 O ; oxyhexic, 3 Ce Hg 03-(-H2 O ; 

 oxyheptic, 3 Cy Hjo O3 + H2 O, and isohexic and isoxyhexic. The 

 constitution of these was worked out to be ; 



CH2— CH2 CH2— CH (CH3) 



CO — CO and CO —CO etc. 



HOFMANN, OTTO, 1880. 



Ann. Chem. 201, 73-89; Ber. 13, 431. 



Action of Zinc and Allyl lodid on Acetoacetic and DiethyI=aceto- 



acetic Esters. 



The action is the same as with .sodium and an alkyl halogen, that is, 

 with acetoacetic ester the mono- and the di-alkyl acetoacetic esters are 

 produced ; Ce Hg (C3 H5) O3 and Ce Hs (C3 K^)^ O3. when allyl iodid 

 is used. When the diallyl acetoacetic ester is treated with zinc and 

 allyl iodid, diallyl acetic ester, CH (C3 ^[5)2 CO2 C2 H^ is produced. 



