230 COMPOUND UREAS. 



COMPOUND UREAS. 



In urea, one, two, or three atoms of hydrogen can 

 still be replaced by means of alcohol or acid radicles. 

 If, for instance, a solution of potasssium cyanate is 

 evaporated with methylamine sulphate, instead of with 

 ammonium sulphate, an urea is produced, which, to 

 gether with the radicle CO, contains the radicle methyl. 

 A large number of such compounds are known, of 

 which only a few will be described here. They all 

 show the greatest analogy with urea in their conduct 

 towards reagents and in their decompositions. 



Ethyl-urea, Co* is produced by the 



decomposition of potassium cyanate by means of ethyl- 

 amine sulphate; and by the action of ethyl cyanate on 

 aqueous ammonia. Large prisms, easily soluble in 

 water and alcohol ; fuses at 92; not volatile without 

 decomposition. Is not precipitated from its solution 

 by means of nitric acid ; when evaporated with nitric 

 acid, however, it yields a crystalline nitrate. 



Diethyl-urea, CO - is formed 



action of ethyl cyanate on ethylamine; and by the 

 decomposition of the former by means of water or 

 sulphydric acid, in which case ethylamine always 

 results at first. Long prisms, which fuse at 112.5, 

 and boil undecomposed at 263. Easily soluble in 

 water and alcohol. Is decomposed by boiling with 

 water, yielding ethylamine and carbonic acid. A 



diethyl-urea CO j- ~^ 2 isomeric with the one de 



scribed, is produced by the decomposition of potassium 

 cyanate with diethylamine sulphate. It is resolved 

 into carbonic acid, ammonia, and diethylamine by 

 boiling with alkalies. 



Triethyl-urea, CO I ^^^H 5 is P roduced b ^ the 

 action of ethyl cyanate on diethylamine. Crystalline ; 



