268 BENZENE. 



vapor. Nascent hydrogen converts it into anilin and 

 ammonia. 



Diazochlor-, Diazobrom-, Diazoiodo-, and Dia- 

 zonitrobenzene-compounds are formed by the action 

 of nitrous acid on the substitution-products of anilin. 

 They conduct themselves in every respect like the 

 djazo-compounds described. 



Azobenzene, C 12 H 10 N 2 , is produced from nitroben- 

 zene by the action of sodium-amalgam, alcoholic 

 potassa or acetic acid, and a great deal of iron ; from 

 anilin hydrochlorate by oxidation with potassium 

 hypermanganate. Large, red crystals, fusing at 66.5. 

 Distills without decomposition at 293. Insoluble in 

 water, easily soluble in alcohol and ether. Combines 

 with bromine, without elimination of hydrogen, form- 

 ing golden-yellow needles of C 12 H 10 Br 2 N 2 , which fuse 

 at 205. Nitric acid converts azobenzene into nitro- 

 substitution-products. 



Amido-azobenzene, C 12 H n N 3 = C 12 

 (Amidodiphenylimide), is produced from the isomeric 

 compound diazoamidobenzene, when the latter is al- 

 lowed to stand for several days with alcohol and some 

 salt of anilin. It is hence formed together with diazo- 

 amidobenzene, and under certain circumstances exclu- 

 sively by treating anilin with nitrous acid. It is also 

 formed by the oxidation of anilin with sodium stannate, 

 or bromine vapor. Yellow, rhombic prisms. Almost 

 insoluble in water, easily soluble in alcohol and ether. 

 Fuses at 127.4. Monatomic base. Is the principal 

 constituent of the dye known as anilin-yellow. 



Azoxybenzene, C 12 H 10 N 2 0, is produced from nitro- 

 benzene, like azobenzene and usually both are formed 

 together. Long, yellow needles, insoluble in water, 

 easily soluble in alcohol and ether. Fuses at 36, and 

 yields by distillation, anilin and azobenzene. Treated 

 with reducing substances, it is converted into azoben- 

 zene and hydrazobenzene. 



