Dr. A. W. Hofmann on Aromatic Monamines. 



47 



December 5, 1872. 



Rear-Admiral G. H. RICHARDS, C.B., Vice-President, in 



the Chair. 



It was announced from the Chair that the President had appointed as 

 Vice-Presidents : — 



The Treasurer. 

 Mr. Busk. 

 Dr. Hirst. 

 Admiral Richards. 

 Dr. Sibson. 



The following communications were read : — 



I. " Synthesis of Aromatic Monamines by Intramolecular Atomic 

 Interchange." By A. W. Hofmann, M.D., LL.D., F.R.S. 

 Received August 22, 1872. 



In a paper submitted to the German Chemical Society about a year 

 ago, we proved (Dr. Martius and myself*) that the action of methylic 

 alcohol on aniline chlorhydrate at a high temperature and under pressure, 

 far from yielding exclusively methyl- and dimethylaniline, as had been 

 formerly believed, is capable of causing methylation of the phenyl group, 

 and thus producing quite a series of higher homologues of dimethylaniline. 



If we endeavour to gain an insight into the mechanism of this reaction, 

 we are led to assume that in the first instance the chlorhydric acid of the 

 aniline salt gives rise to the formation of methylic chloride, which in its 

 turn induces substitution, first in the ammonia fragment, and ultimately 

 in the phenyl group itself. If, on the other hand, we remember that a 

 tertiary monamine, such as must be formed by the final methylation of the 

 ammonia fragment in aniline, when submitted to the action of an alcohol 

 chloride, is invariably converted into an ammonium compound, it must 

 appear rather strange that, in the process above alluded to, only tertiary, 

 and never any quartary bases are observed. 



Under these circumstances the idea very naturally suggested itself of 

 submitting the behaviour of quartary compounds at a high temperature 

 under pressure to an experimental investigation. 



The simplest compound that could be selected for such an inquiry 

 appeared to be trimethylphenylammonium iodide. 



C 6 H t .CH 3 .CH 3 .CH 3 M. 



Reserving for a future communication the experimental details of this 



* Hofmann and Martius, Berichte, 1871, p. 742, 

 TOL. XXI. E 



