216 A GENERAL REVIEW OF 



similar conditions to the above, and apparently the homologue 

 of ethyl /3-ethoxycrotonate was not one of the products. A 

 modification of the usual alkylation process was tried by 

 adding silver oxide to a mixture of ethyl acetoacetate and 

 ethyliodoacetate. It was found necessary to cool the flask 

 containing the reaction mixture and latterly to add benzene 

 for the purpose of lowering the temperature. The product 

 was purified by distillation in a vacuum and ethyl aceto- 

 succinate was thus obtained. Silver oxide can therefore be 

 substituted for sodium ethoxide in the synthesis of acyl- 

 substituted succinic esters. 



In contact with silver oxide and ethyl iodide, ethyl malon- 

 ate does not react in the hydroxy-form to give /3-diethoxy- 

 acrylate, but yields ethyl ethylmalonate as the sole product 

 (loc. cit.). 



Ethyl oxaloacetate and its silver derivative show similar be- 

 haviour in being completely converted by silver oxide and ethyl 

 iodide into ethyl ethoxyf umarate EtOOC . C(OEt) : CH . COOEt, 

 which is also exclusively formed by interaction of the silver 

 derivative and ethyl iodide. No C-ester is formed in either 

 of the above reactions (Lander (17) ). 



The unsuccessful attempts to obtain alkylation derivatives 

 of deoxybenzoin have already been referred to in the section 

 dealing with benzoin derivatives. 



THE MECHANISM OF THE REACTION 



Prior to the discovery of the silver oxide reaction, dry 

 silver oxide had been used as a synthetical reagent by Wurtz 

 in the formation of ethyl ether from ethyl iodide (Ann. Chem. 

 Phys., 1856, iii. 46, 222), by Erlenmeyer for a similar purpose 

 (Annalen, 1863, 126, 306), and by Linneman (Annalen, 1872, 

 161, 37). In preparing isopropyl ether, Erlenmeyer used 

 moist silver oxide. It is stated by Wurtz that dry silver 



