Dr. Hofmann on a new Mode of forming Triethylamine. 71 



which were communicated to the Royal Society, have been, by 

 circumstances, interrupted for some time. Nearly all the observa- 

 tions recorded in my communications refer to the primary or amido- 

 gen-bases, i. e. the compound ammonias, in which I equivalent of 

 hydrogen is replaced by an organic molecule. Of the secondary and 

 tertiary bases (imidogen- and nitrile-bases), i. e. the ammonias in 

 which 2 or 3 equivalents of hydrogen are replaced, and of the fixed 

 ammonium-bases, little more is knowni at present than their mode of 

 formation and their composition. 



On again taking up this subject lately, it appeared of paramount 

 importance to search for new and, if possible, simpler methods of 

 forming the secondary and tertiary bases. 



Of the several experiments made for this purpose, on which I 

 intend to report at another opportunity, I may be allowed even 

 now to quote a result which appears to be capable of a more general 

 application. 



One of the common methods of preparing the amidogen-bases, 

 consists in treating cyanic ether with hydrate of potassa, a reaction 

 which was first observed bj-Wurtz. To take a special case, cyanate of 

 ethyle, when treated ^ith hydrate of potassa, assimilates 2 equivalents 

 of water and splits into ethylamine, which is set free, and carbonic 

 acid, which is fixed by the alkali. An appropriate modification 

 of this reaction appeared to afford a means of passing directly 

 from cyanate of etliyle to triethylamine. For this purpose it was 

 only necessary to offer to the cyanate of ethyle 2 equivalents of oxide 

 of ethyle instead of 2 equivalents of water. The action of cyanate 

 of ethyle upon ethylic potassa appeared to involve the conditions 

 necessary for accomplishing this result. 



Experiment has fully confirmed this anticipation. 



On digesting for several hours at a moderate temperature a mix- 

 ture of pure cyanate of ethyle with pure ethylic })0tassa or soda (that 

 is, absolute alcohol as far as possible, saturated with potassium or 

 sodium), and distilling subsequently upon a sand-bath, a strongly 

 alkaline liquid containing alcohol is obtained. Saturated with 

 hydrochloric acid, this liquid furnishes on evaporation to dryness a 

 residue from which a considerable quantity of trietlujlamine is ex- 

 pelled on addition of potassa. 



The analogy of the two processes, of the formation of ethylamine 

 and triethylamine, is obvious on glancing at the following equations. 



CoENO., -f 2(K0, IIO) = N ^ II -f- 2KCO3 



In 



Cyanate of ethyle. Hydrate of Ethylamine. Carbonate of 



potassa. potassium. 



CoENO, + 2(K0,E0) = N -^ E + 2KCO3 



Cyanate of etliyle. Ethylic Triothyl- Carbonate of 



potassa. amine. potassium. 



