ACTION OF THE HALOGENS, ETC. 175 



Bkominpj Addition Pkoducts of the Bases. 



[a.). From Pakatoluthiochinanthrene. 



When bromine is allowed to drop into a hot acetic acid solution 

 of the base, a point. is soon reached at which suddenly bright red 

 crystals of a bromine addition product separate out. As has before 

 been stated, it is impossible to obtain accurate analyses of these, be- 

 cause, as soon as they are removed from the mother liquor, they begin 

 to give off bromine. A bromine determination showed however that 

 they contain more than four bromine atoms to the molecule. By 

 heating them at 100°, they lose bromine and hydrobromic acid, and 

 there is formed a mixture of the free base and the hydrobromic acid 

 salt. By further heating all bromine is driven off. 



Bromine Determination. 



.1474 grms. substance gave by the method of Carius .1807 grms. 

 Ag Br. 



Computed : Found : 



CooHj,N,S„ 2HBr, Br,, 



6Br:=58%. 52.09%. 



C,„H,,N,S„ 2HBr, Br„ 



4Br=-48%. 



(b). From Thiochinanthrene. 



A similar experiment with thiochinanthrene gave a beautifully 

 crystallized red bromine body, which also gives off bromine as soon 

 as it is removed from the Solution. The compound showed by 

 analysis more than live atoms of bromine. In this case however, the 

 pure HBr salt was obtained by heating the product to constant 

 weight at 115°. 



Bromine Determination. 



.1512 grms. substance gave .1992 grms. Ag Br. 

 Computed: Found: 



C,H„N,S„ 2IIBr, Br„ 



6Br=67.6%. 56.07 7^. 



5Br=55.7%. 



