[ 125 ] 



No. 16. 



THE ACTION OF THE OXIDES AND THE OXYACIDS OF NITEOGEN 

 ON ETHYL-PHENYLUEETHANE. 



By HUGH EYAN, D.Sc, 



AND 



ANNA CONNOLLY, M.Sc, 

 University College, Dublin. 



[Read December 19, 1922. Printed February 22, 1923.] 



Introduction. 



It has been found by one of us, in conjunction with N. Cullinane (p. 119), that 

 ethyl-otolylurethane undergoes little, if any, direct nitration. The nitrating 

 agent appears to remove the ethyl radical by oxidation to oxalic acid, and then 

 gives nitro derivatives of o-tolylurethane only. 



Nitration and oxidation of the urethane could occur simultaneously. It is 

 probable, however, that the directive influence of the methyl radical in the posi- 

 tion 2 impeded the formation of a 4-nitro derivative of the original urethane 



CH3 

 ./ 



i\ N COOC2HS 



/ I 



CjHs 



A retardation from such a cause in the speed of nitration of a tertiary urethane 

 would make the oxidation reaction preponderant, and in this way an explanation 

 would be got for the apparent formation of derivatives of only the secondary 

 urethane. Indications that this explanation may be correct have been obtained 

 from a study of the behaviour of ethyl-phenylurethane. 



The latter substance, which is a dense, colourless oil, has, so far as we are 

 aware, been hitherto studied only by 0. Schmidt [Ber. Dtsch. Chem. Ges., 

 xxxvi (1903), p. 2477], who examined some of its physical properties. 



Nitrogen peroxide converted ethyl-phenylurethane in carbon tetrachloride 

 solution into ethyl-4-nitro-phenylurethane, the constitution of which was 

 established by its conversion into p.-nitro-ethylaniline. 



In the same reaction a very small quantity of a less soluble, crystalline solid, 

 melting at 88° C, was obtained. This proved to be a dinitro-ethyl-phenyl- 

 urethane. 



The same two compounds, 4-nitro-ethyl-phenylurethane and dinitro-ethyl- 

 phenylurctbane, were obtained by the action of fuming nitric acid on ethyl- 

 phenylurethane. 



On the other hand, a mixture of concentrated sulphuric and nitric acids 

 converted 4-nitro-ethyl-phenylurethane into the same dinitro- and trinitro-phenyl- 



SOIENT. PECO. K.D.S,, VOL. XVII, NO. 16. 2 A 



