120 Mr Sell, The Ghlorination of Methyl derivatives, etc. 



trichlorpicolinic acid when distilled with glycerol breaks down, 

 producing carbon dioxide and a trichlorpyridine, melting at 72 

 — 73°, produced not only by the direct chlorination of pyridine, 

 but also by the action of phosphorus pentachloride on that sub- 

 stance (Trans. Ghem. Soc. 1898, 73, 442). 



From the highly basic and other properties of this trichlor- 

 pyridine it was suspected that the chlorine atoms in the molecule 

 occupied the positions 3, 4, 5, and the experimental verification of 

 this surmise was carried out as follows : 



We may take for comparison the substance 2-amino 3, 4, 5 

 trichlorpyridine whose formula maybe thus depicted (Trans. Ghem. 

 Soc. 1899, 75, 980; 1900, 77, 771): 



Cl 



CI 



Cl 



NIL, 



This compound should also be obtainable from the trichlor- 

 picolinic acid mentioned above by first converting it into its amide, 

 and then by the " Hofmann reaction " into amino-trichlorpyridine. 

 These reactions were carefully carried out and resulted in a 

 substance identical with the compound whose graphic formula 

 is above depicted. We may, therefore, formulate the three 

 substances which are the subject of this paper as follows: 



Cl 



Cl 



Cl 



H 



Cl 



CC1 S 



Cl 



H 



Cl 



COOH H 



N 



H 



