Macbeth and Graham — Action of Sulphui- Chloride on Ammonia. 39 



Substance. 



Coloration 



Phenylliydrazine. 



Benzylphenylhydraziiie. 



Diazoaminobenzene. 



Aminoazobenzene. 



Red-brown precipitate (in benzene). 

 Yellow precipitate (in chloroform). 



Chocolate precipitate (in benzene). 

 Yeiluw precipitate (in chloroform). 



Yellow precipitate (in benzene). 

 Yellow-brown precipitate (in chloroform). 

 Orange-red precipitate (in carbon disulphide). 



Chocolate precipitate (in benzene). 



Maroon precipitate, (in chloroform) . 



Itagenta, with a metallic sheen (in carbon disulpldde). 



Aromatic compounds containing an acid group in the molecule do not 

 produce coloured precipitates with sulphur chloride. For example, sulphanilic 

 acid and the three amino-benzoic acids give at the most a slight white 

 precipitate on treatment with the reagent. The nitranilines behave in a 

 similar way. When the hydrogens of the amino group are replaced, as in 

 acetanilide, /)-acetotoluidide, formanilide, &c., no reaction takes place : this 

 is to be expected in the light of the course of the reaction already established 

 in the case of the parent bases. 



Colour production is also inhibited when the NH^-group is part of an 

 acid amide. Xo colour is formed in such cases, even when the sulphur 

 chloride is added direct to the solid amide. Urea, thiourea, and theii' 

 substituted derivatives also behave in this way. 



Substances containing a tertiary nitrogen atom as a ring member give 

 precipitates in benzene solution with sulphur chloride : these are white and 

 are soluble in chloroform. Such results have been obtained with pyridine, 

 collidine, quinoline, and a- and /3-picoline. 



Edinger^ has investigated this reaction in the case of quinoline and 

 methylquinoline. The product obtained on heating these substances with 

 sulphur chloride in a sealed tube consists of a mixture of chlorinated 

 compounds and a substance CisHioNaSj, to which he ascribes the constitution 



\s/ 



C9H5N/ \NC9H5 



1 Berichte d. Deutsch. Chem. Gesell., 1896, 29, 2456 ; 1897, 30, 2418 ; J. pr. Chem., 

 1896, [2] 54, 340. 



R.I. A. PROC. VOL. .'CXXVI, SECT. B. 



in 



