1864.] in which Nitrogen is substituted for Hydrogen. 381. 



nate of sodium, 



€3 H, N, HBr3=€3 H, Br + + Br.. 



V , ' ^ 



Dibromide. Bromobenzol. 



The same change may also be effected by simply boiling an alcoholic 

 solution of the dibromide. 



The peculiar and often remarkable properties of the diazobenzole- com- 

 pounds have induced me to try whether analogous bodies could not be pre- 

 pared also from bromaniline, nitraniline, dibrom aniline, &c. Experiment 

 has fully borne out theory. These analogous diazo-substitutions exhibit, 

 however, so much resemblance to the normal diazobenzol compounds, that 

 I should frequently have to repeat almost literally what has already been 

 said of the latter, were I to describe these compounds in detail. I may be 

 permitted, however, to mention a remarkable and interesting fact which their 

 investigation prominently bronght out. There are, as is well known, two 

 isomeric nitranilines — the alphanitraniline of Arppe, and the betanitraniline 

 of Hofmann and Muspratt. This isomerism, I found, extends itself to 

 their respective nitrogen-substitution compounds, and even to their pro- 

 ducts of decomposition. On heating, ea:. gr., the dibromide of alphadiazo- 

 nitrobenzol with alcohol, the following change takes place : — 

 H3 (NOJ N, HBr3=€3 H, (NO,) Br+N,+Br,. 



^ ^ ^ -^r ' 



a-dibromide. Broraonitrobenzol. 

 The bromonitrobenzol thus obtained is identical with that prepared by 

 Cooper from benzol derived from coal-tar. It crystallizes in the same form, 

 and fuses, like the latter, at 126° C; sulphide of ammonium converts it 

 into bromaniline, which crystallizes in octahedra, and is identical with the 

 bromaniline of Hofmann obtained from bromisatine. Bromonitrobenzol, 

 prepared in a perfectly similar manner by the decomposition of the dibro- 

 mide of betadiazonitrobenzol, possesses, however, widely different properties. 

 The a-bromonitrobenzol just described crystallizes in long needles, whilst the 

 new benzol-derivative, which I will designate by the name of /3-bromonitro- 

 benzol, forms well-developed prisms, the fusing-point of which lies at 56°C. 

 Sulphide of ammonium converts it likewise into bromaniline ; but this 

 base differs in its physical properties entirely from the bromanihne obtained 

 by Hofmann. It forms a colourless oil, which combines with acids, and 

 gives rise to a series of beautiful salts, which in their turn differ greatly 

 from the ordinary bromaniline salts in their physical properties. I will 

 distinguish this bromaniline hj calling it /3-bromaniline from that obtained 

 by Hofmann, which I will call a-bromaniline. 



It deserves to be mentioned briefly that there exist likewise two isomeric 

 chloronitrobenzols (alpha and beta) obtained by heating the platinum-salts 

 of the respective diazonitrobenzole with carbonate of sodium, 



€3 H3 (NO,) N„ HCl, PtCl,=Ce H, (NO,) CI + N, -f PtCl,. 



V . V ; 



«, /S Platinum-salt. a, /8 Chloronitrobenzol. 



