214 A GENERAL REVIEW OF 



The silver oxide reaction has also proved to be of use in 

 the preparation of certain of the aliphatic imino-ethers, which, 

 as a class, are difficult to isolate and identify, by reason of their 

 fugitive nature. If ethyl oxamate is treated with ethyl iodide 

 and silver oxide a vigorous reaction ensues, and Nef's semi- 

 imino-oxalic diethyl ether C : NH(OEt) . C0 2 Et is produced (7). 

 Acetamide undergoes decomposition under the same condi- 

 tions. Alkylation of urethane takes place at the ordinary 

 temperature if the substance is dissolved in a mixture of ethyl 

 iodide and dry ether and the solution allowed to stand in 

 contact with silver oxide for ten days. The product, imino- 

 carbonic diethyl ether (C 2 H 5 0) 2 : C : NH, is isolated in the form 

 of the bromimino-ether. 



It is seen that ethylation of substituted amides by silver 

 oxide and ethyl iodide under the usual conditions gives imino- 

 ethers . C(OEt) : N almost exclusively, while on substituting 

 methyl for ethyl iodide imino-ethers and isomeric substituted 

 amides are produced at the same time. It is however possible, 

 as Lander (17) has shown, by conducting the alkylation at 

 100 C., to obtain both ethyl homologues PhN : C(OEt) . Me 

 and PhNEt . CO . Me simultaneously, by the action of silver 

 oxide and ethyl iodide on acetanilide. The results thus 

 resemble those obtained by the methylation of the substance 

 in an open vessel at 40-50 C. 



For comparative purposes, Lander investigated the action 

 of silver oxide and methyl iodide on formanilide, and obtained 

 N-phenylformiminomethyl ether H . C(OMe) : N . C 6 H 5 mixed 

 with a small quantity of the isomeric amide H . CO . NMe . C 6 H 5 

 and some diphenylformamidine. When silver formanilide 

 was boiled with ether and methyl iodide, a small quantity 

 of imino-ether was formed, more of the amide and considerably 

 more of the amidine than in the former experiment. These 

 results are of considerable theoretical significance. 



