432 



solution of dimetlijlainiiiobeiizaldeliyde there appears, however, a 

 red-violet colour. 



Metallic potassium acts on this substance: a potassium compound 

 is formed, as is to be expected. For this purpose we dissolved the 

 substance in toluene, and let the potassium act at the boiling tem- 

 perature of the solution. At first the action proceeds pretty rapidly, 

 but it soon slows down, so tliat the heating must be prolonged. 

 The potassium compound was deposited as an insoluble yellow- 

 brown powder. 



In order to ascertain the structuie of the C-(«-pyridyl)-pyrrole, 

 we have oxidized two grammes of this substance with potassium 

 [)erinangaiiate in sulphuric acid solution. The oxidation takes place 

 very readily at the ordinary temperature. Out of the reaction product 

 we have isolated the characteristic violet copper salt of picolinic 

 acid, and from this salt we freed the picolinic acid itself by addition 

 of sulphuretted hydrogen. The picolinic acid thus obtained was 

 sublimated in order to ()urify it. The sublimated preparation melted 

 at 134°. 2, while we found 136°. 8 for the melting-point of picolinic 

 acid obtained by oxidation of picoline. The melting-point of the 

 mixture of these two preparations was 132.5° — 133°. The nitrogen 

 percentage of our preparation that melted at 134.2, was 11.25 °/„ 

 (calculated for picolinic acid 11.38 "/„). In spite of the slightly too 

 low melting-point there is no doubt of the identity of our prepara- 

 tion ; the characteristically crystallizing platinum salt had exactly 

 the same api)earance as the platinum salt of the picolinic acid 

 prepared from picoline. It appears from this that in the pyrrole 

 derivative melting at 90° the pyrrole nucleus is united to the '(-C-atom 

 of the pyridine nucleus. 



We have prepared a picrate from this pyridyl pyrrole, which 

 was obtained after recrystallisation from alcohol as fine, yellow 

 needles of the melting-point 227 — 228°. 



We have prepared the iodine methylate of the pyridyl pyrrole 

 melting at 90° by heating this pyrrole derivative in methyl alcoholic 

 solution with an excess of methyl iodide at 100° for three hours. 

 After evaporation of the solvent and of the superfluous methyl iodide 

 the reaction product was recrystallized from methyl alcohol; in this 

 way yellow.-brown hard prism-shaped crystals were obtained, which 

 melt at 148°. We found 9,67, for the nitrogen content, and 44.7 7» 

 lor the iodine content. The calculated values for C,oH,,N, J are 

 N : 9,73 7, ; J : 44,37 7,. This substance has, therefore, been formed 

 by the addition of one molecule of methyl iodide-, the group 

 ('11 ,1 is combined with the nitrogen atom of the pyridine nucleus. 



