120 BIBLIOGRAPHY OF 



HANTZSCH, A., 1890. 

 Ber 23, 2339-2342; J. Chem. Soc. 58, 1238. 

 Halogen Derivatives of Acetoacetic Ester. 



The action of thiocarbamid and thioacetamid on the halogen 

 derivatives of acetoacetic ester are used to distinguish between the a 

 and y positions for the halogen thus: 



CH^Br HS CH-S 



II II I 



CO + C-CNH^or CH3)= C C-CNH^orCHj) 



\ ^/ I \ // 



CO2RCH2 HN CO2R-CH2N 



which is amido- or methyl- thiazylacetic ester and 



CO^R-CHBr HS CO^ RC-S 



II II I 



CH3CO + C-CNH^or CH3)= CH3C C-INH^ or CH3). 



HN N 



Bromin acting on acetoacetic ester gives the y product but when 

 cupracetoacetic ester is treated with bromin the a product is obtained. 

 Chlorin acting on acetoacetic ester gives the a product. Methyl-ethyl- 

 thiazole, 



CH-S 



C-CH3. 



C3H5 N 



was produced from methyl-brom-acetoacetic ester showing it to be the 

 }' product and trimethyl-thiazole, 



CH3-C-S 



CH3 C CCH3 , 



\// 



N 



was produced from methyl-chlor-acetoacetic ester showing it to be the 

 a derivative. 



