Bell — On. a Series of Bases derived from Pyrrol. 45- 



to the very sparing solubility of diamylamine in water, the greater- 

 part of it formed a layer on the top of the distillate. This layer 

 included a not inconsiderable quantity of amyl-pyrrol and of diamyl- 

 carbo-pyrrol-amide, no doubt due to the presence of amylamine in the 

 salt operated upon. They were easily detected and isolated, when the 

 diamylamine was converted into hydrochlorate. The retort-residue 

 presented the appearance previously described. 



Distillation of Triethylummonkim Mucate. 



Although in view of the results obtained with the secondary 

 amines little could be expected from the experiment, I have never- 

 theless, for the sake of completeness, executed it. 



Triethylamine combines with mucic acid to form an extremely 

 soluble compound, which crystallizes in long prisms. On heating a 

 strong solution of the salt it undergoes dissociation (decomposition ?), 

 triethylamine being given off, while the liquid becomes strongly acid. 

 "When distilled in the paraffin bath this salt also decomposed at about 

 170°, the sole products being a carbonaceous residue, as before, and a 

 clear solution of triethylia carbonate, on the surface of which floated 

 some free triethylia. The residue, which resembled in appearance 

 and properties those previously obtained, was not minutely examined. 



It is now clear that the primary amine salts of mucic acid are alone 

 capable of furnishing by distillation derivatives of pyrrol. The fact 

 that these derivatives are generated at a lower temperature, and with 

 fewer secondary products, than pyrrol itself from ammonium mucate, 

 strengthens us, I think, in the conviction that the group C4H4, exist- 

 ing in them, must in some way form the base on which the molecules 

 of mucic acid, galactose, and possibly of many other sugars, are con- 

 structed. 



It is quite evident that the methyl, ethyl, and amyl groups in these 

 derivatives must stand in dii'ect connexion with the nitrogen. In fact 

 the bases of this series cannot be regarded as true homologues of 

 pyrrol, since the fatty radicles are simply introduced into the lateral 

 chain = I^H, and not into the hydi'ocarbon nucleus. In this respect 

 it is interesting to contrast their boiling points and other physical 

 properties. It will be observed that the introduction of the methyl 

 group into the pyrrol molecule at once lowers the boiling point about 

 21°, instead of raising it ; but that, starting from methyl-pyrrol, the 

 boiling points exhibit approximately the common difference of 19° 

 for each addition of CII2. 



Boiling Points. Difference from preceding Term. 



Pyrrol, ... 133° — 



Methyl-pyrrol, 112-113° 

 Ethyl-pyrrol, .131 

 Amyl-pyrrol, . 180-184 



- 20° 



to - 21° 



+ 18 



to + 19 



+ 17 



X 3 9. p 



