304 REPORT — 1900. 



In support of this conclusion there may be advanced a number of 

 well-established facts, and the necessity for the discussion of the points 

 involved may be made the occasion for introducing the nomenclature 

 necessary for reference to the derivative of camphoric acid. 



1. Camphor Acid contains only one Hydrogen Atom in the 



a-PoSITION AVITH REGARD TO A CaRBOXYL GrOUP. 



(a) Bromination of Camphoric Acid. 



Camphoric acid is capable of affording, by direct bromination, one, 

 and only one, monobromo-derivative, zc-bromocamphoric acid. From 

 the study of a very large number of acids it has been ascertained that it 

 is possible to introduce as many bromine atoms as there are hydrogen 

 atoms in the a-position with regard to carboxyl groups, and in each 

 case where the products have been completely investigated it has been 

 shown that the entrant bromine atoms occupy the a-position. The 

 conclusion thus derived regarding camphoric acid is confirmed by a 

 large number of observations, and there is no sufficient reason to imagine 

 that the bromination of camphoric acid pursues any but the normal 

 course. 



(b) Differential Reactivity of the two Carhoxyl Groups. 



Camphoric anhydride on treatment with ammonia yields exclusively, 

 or almost exclusively, a-camphoramic acid. This on distillation loses 

 water, yielding camphorimide, which when subjected to alkaline hydro- 

 lysis affords only /j-camphoramic acid. 



The reactivity of carboxyl or carboxyl groups in aliphatic compounds 

 invariably appears great or small according as the adjacent carbon 

 atom is hydrogenised or not. The above observations, which show that 

 there is an enormous difference between the reactivity of the carboxyl 

 groups in the anhydro-camphoric derivatives, are doubtless accounted 

 for by the fact that only one of the two carboxyl groups of camphoric 

 acid is an attachment to a hydrogenised carbon atom. On this assump- 

 tion the course of the changes referred to may probably be expressed 

 as follows : — 



OH O 



/ / 



CH.CO. CH.C.NH2 CH.C.NH2 



\ 



+ NH3-> ; \o 



C .Co/ ^ C .CO/ C .CO. OH 



C c c 



Camphoric Anhydride. Hypothetical Addition a-Camphoramic Acid. 



Compound. 



O 



/ 



CH.G 



C.CO/ C.CO/ C.CO.NH, 



NH + H2O 



C . CO/ 



c 



Campliorimide. )3-Camphoramic Acid. 



