194 Drs. Muspratt and Hofmann on Toluidine. 



attention to a remarkable way for obtaining aniline, and which 

 we discovered during our experiments. 



Chemists are well acquainted with the interesting compound 

 Mitscherlich described under the name of azobenzide in one 

 of his beautiful papers upon the derivatives of benzoic acid. 

 He obtained this body by distilling nitrobenzide with alcohol 

 and potash, together with other products which were not fur- 

 ther investigated. Azobenzide differs only from aniline in 

 two equivalents of hydrogen. 



Aniline . . . C^g H^ N . '^ 



Azobenzide . . Cjg H5 N. ' '^ 



In order to see if a closer relation did not subsist between 

 these two bodies, we prepared large quantities of azobenzide, 

 following Mitscherlich's directions throughout, and obtained 

 this body, possessing all the properties ascribed to it by that 

 chemist. 



On more closely examining the secondary products formed 

 dui'ing this process, we found that besides other substances 

 there is likewise produced a very large quantity of aniline, 

 and the residue contains a considerable quantity o^ oxalic acid. 



These observations appear to shed more light upon the 

 manner in which the azobenzide is formed, i. e. if we assume 

 that the oxalic acid is produced from the alcohol at the ex- 

 pense of the oxygen of the nitrobenzide : 2 equivalents of 

 nitrobenzide and 1 equivalent of alcohol contain the elements 

 of 1 equivalent of azobenzide, 1 equivalent of aniline, 2 equi- 

 valents of oxalic acid, and 2 equivalents of water, as shown 

 in the subjoined equation, — 



2 (C,2 H5 NO4) + C4 H, O HO = ' 



Nitrobenzide. Alcohol. 



C,2 H5 N + C12 H7 N + 2 (C^ O3, HO) + 2 HO. 



Azobenzide. Aniline. Oxalic acid. 



We are far from supposing that the above equation repre- 

 sents the true decomposition, as other products are formed ; 

 and further, the aniline distils over long before a trace of ox- 

 alic acid is detectable in the retort. The true transformation 

 can only be given when all the products of this complex re- 

 action are investigated. We are at present engaged upoD 

 this subject, and expect shortly to solve the problem. ,'^ 



