ACETO ACETIC ESTER I 3 



soluble in alcohol, ether and benzene, and boils at 254 to 256? When 

 saponified with alcoholic potash, acetic and succinic acids are pro- 

 duced. Barium hydroxid produces /?-aceto-propionic acid CH 3 CO 

 CH 2 CH 2 CO 2 H, a crystalline substance which melts at 31? This is 

 probably the same as the levolinic acid of Grote and Tollens (Ann. 

 Chem. I75> 181) The ethyl ester was also produced. 



CONRAD, M, 1877. 



Ann. Chem. 188, 226-228 ; J. Chem. Soc. 34, 137. 

 Synthesis of Pyrotartaric Acid from Acetoacetic Ester. 



When sodacetoacetic ester is treated with a-brom-propionic ester, 

 ^-methyl-aceto-succinic ester is formed, thus: CH 3 CO C H Na CO 2 

 C 2 H 5 + CH 3 C H Br CO 2 C 2 H 5 = CH 3 



CO CH 3 



CH- CH 

 C0 2 C 2 H 5 CO 2 C 2 H 5 



,2- Methyl aceto-succinic ester is acted upon by barium hydroxid and 

 the barium salt of pyrotartaric acid is formed. 



ROHRBECK, HERMANN, 1877. 



Ann. Chem. 188, 229-239 ; J. Chem. Soc. 34 136. 



tt-Methyl ^9-Oxybutyric Acid and =Methyl Crotonic Acid. 



a- Methyl /9-oxy butyric acid was obtained from methyl-acetoacetic 

 ester by the action of sodium amalgam and when heated this a-methyl 

 /9-oxy butyric acid was changed into a-methyl crotonic acid, CH 3 CH : C 

 CH 3 CO 2 H. The properties and salts of each acid were described. 



WALDSCHMIDT, ERNST, 1877. 



Ann. Chem. 188, 240-248 ; J. Chem. Soc. 34. 136. 



Reactions of Acetoacetic Ester. 



tt-Ethyl /9-oxybutyric acid and a-ethyl-crotonic acid were produced 

 from acetoacetic ester, the reactions being similar to those of Rohrbeck* 

 which proves that they are general. The salts of these two acids were 

 studied and described. 

 *See pages 7 and 13. 



