100 BIBLIOGRAPHY OF 



and a subsequent separation of hydrochloric acid forming a lactone. 



In the formation of sodacetoacetic ester an aldol polymerization is 



supposed to take place first, the product of which is acted upon by 



/ OC3 H5 

 sodium thus : — 2 CH3 CO^ C, H5=CH3 C CH, CO^ C^ H5, then 



sodium forms CH3 C CH2 CO2 C2 H5 , which is again acted upon by 



\ONa 

 sodium to form CH3 CONaCHCO^ C^ H5 , NaOC, H5 and H. If sodium 

 be made to act on acetoacetic ester, CH3 COCHNaCOa C2 H5 is formed 

 but the sodium is immediately attracted to the carbonyl group and it 

 changes to form CH3 CONarCHCOa C2 H5. When this last compound 

 is treated with an alkyl iodid, C2 H5 i for example, there is an addition 

 product formed and as the group — CONa=is more positive than the 

 group=CH — , the iodin add to the former and the ethyl adds to the 



/ONa 

 = CH— group forming CH3 C CH (C2 H5) CO2 C2 H5 from which 



\ I 

 sodium iodid separates leaving CH3 COCH (C2 H5) CO2 C2 H5. 



POLONOWSKY, M., 1888. 



Ann. Chem. 246, 1-32 ; J. Chem. Soc. 54. 1067 ; Ber. 21, 636 (C). 



Condensation of Glyoxal with Acetoacetic Esters. 



By treating a mixture of glyoxal, CHOCHO, and acetoacetic ester 

 with zinc chlorid two products are formed, (i) a part soluble in alkalis 

 which contains methyl-furfuran carboxyacetic or sylvanecarboxyacetic 



acid, 0<^.^^^==.9^^^(^'^>, which melts at 207° The normal 



and acid, methyl and ethyl esters were produced and described ; (2) a 

 part insoluble in alkalis which consists of a heavy oil and a crystalline 

 substance, both having the composition C14 His 06- The oil is di-ethyl- 

 sylvane-carboxy-acetoacetic ester which is : — 

 CH3 



CO CH (CH3) C 



I I ' >o 



CH C: (CO2 C2 H5) C 



I 



CO2 C2 Hr 



