PURDIE'S REACTION 179 



of this method of alkylation was not a chance result, but was 

 due to a careful and systematic tracing of an effect to its 

 cause. 



The reaction was immediately utilised for the preparation 

 of the methyl methoxy- and ethyl ethoxy-propionates (Purdie 

 and Irvine (2) ), and the optical activity of the corresponding 

 acids and their salts was determined and compared with the 

 values obtained for the same compounds which had previously 

 been prepared by resolution of the racemic acids by morphine 

 (Purdie and Lander, Trans., 1898, 73, 862). The comparison 

 indicated that the alkylation process proceeded without any 

 racemisation occurring. At the same time McKenzie (3) was 

 able to prepare inactive and active phenylalkyloxyacetic 

 acids by the alkylation of i- and Z-mandelic acids and their 

 esters. 



In the following year (1900) Lander (4) published the 

 results of an elaborate investigation of the general applica- 

 bility of this method of alkylation. He was able to show 

 that, by treatment with silver oxide and alkyl iodides, it is 

 possible to substitute alkyl groups for the hydrogen in the 

 hydroxyl groups of compounds of such widely different types 

 as /-menthol, i-benzoin, ethyl acetoacetate and salicylic 

 acid. The reaction of benzaldehyde with silver oxide and 

 ethyl iodide leads to the oxidation of the substance and sub- 

 sequent esterification of the resultant acid, ethyl benzoate 

 being obtained. It was further shown that silver oxide and 

 alkyl iodides react with amides and substituted amides, a 

 hydrogen atom being replaced by an alkyl group. Acet- 

 anilide, for instance, yielded N-phenylacetiminoethyl ether 

 C 6 H 5 .N: C(OC 2 H 5 ).CH 3 . The production of imino-ethers is 

 therefore much facilitated by this reaction, since the prepara- 

 tion and isolation of the intermediate silver compounds are 

 obviated. 



The results which have been mentioned rendered it evident 

 that the use of dry silver oxide and alkyl iodides constituted 



