Structure of Simpler Organic Compounds. 129 



amounts of unchanged primary amines). The separation 

 of the volatile products from the quaternary compounds 

 having been accomplished by steam distillation, the 

 primary, secondary, and tertiary derivatives in the distillate 

 are treated with nitrous acid. If the reaction mixture is 

 acidified with hydrochloric acid, the tertiary derivative 

 which is not acted on by nitrous acid forms a hydro- 

 chloride. The nitroso derivative formed from the secondary 

 amine does not, however, form a salt, and can be extracted 

 from the solution by ether, in which the salts are insoluble. 

 From the nitroso derivative obtained in this way, the 

 secondary amine can be regenerated by boiling with hydro- 

 chloric acid 



(C 2 H 5 ) 2 NO + H 2 = (C 2 H 5 ) 2 NH + HO-NO 



The secondary amines resemble generally in properties the 

 primary substances, forming similar salts. Diethylamine 

 has boiling point 56. 



Tertiary Amines. These again are generally similar 

 to the primary and secondary bases. As in the case of so 

 many organic compounds, the boiling points increase with 

 increasing molecular weights. 



Quaternary Ammonium Compounds. Alkyl halogen 

 compounds unite directly with tertiary amines to form 

 these characteristic compounds, which are generally sub- 

 stances which readily crystallize. They are non-volatile. 

 The reaction can be illustrated by the equations 



N(C 2 H 5 ) 3 + C 2 H 5 I = N(C 2 H 5 ) 4 I Tetrethyl ammonium iodide. 



N(C 2 H 5 ) 3 



When such iodides are treated with silver hydroxide, the 

 iodine is replaced by the hydroxyl group. Tetrethyl 

 ammonium hydroxide produced in this way is a crystalline 

 deliquescent substance which is non-volatile. Its solution 

 is a strongly alkaline base, and absorbs carbon dioxide from 



(1,997) 9 



