98 BIBLIOGRAPHY OF 



JAPP, FRANCIS AND FELIX KLINQMANN, 1888. 



Ber. 21, 549-551. 



Formation of Mono- and Di-hydrazin Derivatives of «-Di-ketones. 



Methyl-acetoacetic acid and diazobenzene chlorid, Ce H5 Nj CI, react 

 and form the monophenylhydrazin derivative of diacetyl, 



CH3 COCCH3 



N-NHC6 H5 

 which melts at 133.° If treated with phenylhydrazin the di-phenyl- 

 hydrazin derivative is formed. Ethyl-acetoacetic acid reacts similarly 

 and gives rise to the corresponding compounds. j 



CLAISEN, L. AND N. STYLOS, 1888. 



Ber. 21, 1144-1149; J. Chem. Soc. 54, 671. 



Acetoacetic-aldehyde. 



The sodium compound of acetoacetic-aldehyde, CH3 COCHNaCHO, 

 was prepared from acetone, formic ester and sodium ethoxid. The free 

 aldehyde could not be isolated on account of its tendancy to break down 

 into symmetrical triacetyl benzene, which was made and described. 

 The anilid, toluidid and napthalid of the aldehyde were prepared. 

 Treated with phenylhydrazin, methyl-phenyl-pyrazole, 



CH = CCCHjK^^^ ^^ ^^^ obtained. 



CH = N^ 



PECHMANN, H. v., 1888. 



Ber. 21, 1411-1422; J. Chem. Soc. 54, 811. 

 a-Diketones. 



The diketones described in this article are prepared from monoalkyl 

 acetoacetic esters, by saponifying with dilute alkali, treating the pro- 

 duct with sodium nitrite and sulfuric acid and after removing the alco- 

 hol by distillation, adding twenty times the volume of dilute sulfuric 

 acid and distilling with steam. Methyl-acetoacetic ester treated in this 

 manner gives diacetyl, CH3 COCOCH3, and ethyl-acetoacetic ester gives 

 acetyl-propionyl, CH3 COCOCH^ CH3. 



