70 



KANSAS ACADEMY OF SCIENCE. 



stable and can be isolated. They are soluble in ether, but only 

 slightly so in alcohol, and are purified by washing with alcohol and 

 recrystallizing from a mixture of ether and alcohol. 



A determination for bromine gave the following results : 

 0.2151 grams of the substance gave 0.2100 grams of AgBr. 



Calculated for 

 Ci4Hi3N3Br2. Found. 



41.77% 41.5S% 



A molecular weight determination, by lowering of the freezing- 

 point of benzene, gave the following : 



I. 0.2435 grams caused a depression of 0.223 degrees in the freez- 

 ing-point of 14.13 grams of benzene. 



II. 0.4459 grams caused a depression of 0.42 degrees in the freezing- 

 point of 14.18 grams of benzene. 



Calculated for 

 CHHi3N3Br2. Found. 



1 382.13 378.66 



II . 368.16 



If, as claimed by Griess, aniline treated in this way gives diazo- 

 amido-benzene, then our reaction may be represented as follows : 



I. CeHsCHsBrNHa + HONO = C6H3CH3BrN = NOH+H2O. 

 ?/i-brom-p-toluidine nitrous acid = «i-brom-p-diazotoluene. 



II. CcHsCHsBrN = NOH + C6H3CH3BrNH2 = 



C6H3CEJ3BrN = N — NH — C6H3CH3Br + H20. 

 4, 4' dimethyl 2, 2' dibrom diazo-amido-benzene. 



The substance may be graphically represented: 

 H Br Br 



HsC 



CHs 



