( 603 ) 



boiling with water were decomposed with formation of carbon 

 dioxide and a nitrami no-alcohol. 



CH,— CH, 



The third rule is derived from the behaviour of CH, OH, which 



I I 



CH,— NH 



piperidine 



yields with nitric acid a nitrate, but not directly a nitro-compound. 

 This, however, may be prepared from a number of piperidides, to 

 which we added recently the piperidides of sulphuric and succinic acids, 

 or from the nitrate with acetic anhydride as found by Bamberger. 



CH,-NH— CH, 

 I have noticed recently that behaves in the same 



CH,— NH— CH, 



piper azine. 



manner. 



The above cited new investigations and those which follow origi- 

 nated in a research by Mr. A. Donk. He had prepared for practice 



CH,— NH— CO 



and we treated this with nitric acid. But even 

 CO— NH— CH, 

 glycocol anhydride 



on evaporation on a boiling waterbath it gave no evolution of 

 nitrous oxide, no nitroderivative, but a nitrate. I had expected this 



OH,— NH— CH, 

 behaviour sooner from the unknown | which is one of its 



CO— NH— CO 

 im inodiacetic im ide 

 isomeres, and in which one NH-group is placed between two CO-groups 

 and the other between two saturated hydrocarbon residues, but not 

 from glycocol anhydride in which each NH-group is placed between 

 CO and a hydrocarbon residue, and about whose structure no doubt 

 could be entertained. At most, we might suspect here a tautomer 

 which does not react with nitric acid, or in all other cases in which 

 nitric acid does act we might assume a tautomer and not here. l ) 



Mr. Donk's nitrate, a very loose compound, appeared to be a mono- 

 nitrate, and on applying Bamberger's method for amines (treatment 



J ) Harries 1. c. suspects in 1 N methylhydantoïn a tautomer CHj— N ,v 



i / C0H 



GO -NCR, 

 which, however, yields with nitric acid the same nitromcthylhydantoïn. 



