ON THE CONSTITUTION OK GAMPHOU. 



:n7 



Walker, and Perkiii, but the formula suggested by Tiemann must now be 

 regarded as quite out of the question ; whilst the formula specially 

 advocated by Perkin, whilst greatly preferable, is now known to have 

 no probability in its favour. It is significant that the chemists who at 

 the present day strenuously advocate the acceptance of any formula other 

 than Bredt's have made a special study of isolauronolic acid. 



Latterly chemists have come to regard it as definitely established that 

 camphor contains the grouping 



CMe.O 



CMe„ 



C 



and it is easily demonstrated that besides three formula containing this 

 complex, only one other structure for camphor can be devised which 

 contains the grouping of carbon atoms of camphoronic acid, and also 

 conforms to the established conditions referred to in B, C, and D. 'Jliat 

 formula is 



CH„— CMe.CMe,.CO 



I " I V 



CHo-CH CH, 



but nothing further can be said in favour of it. 



Conclusive proof that the above trimethylpentamethylene nucleus is 

 present in camphor is afibrded by the fact that camphononic acid, which 

 is obtainable from camphor in three entirely different ways, two of these 

 involving no change in the hydrogenised nucleus, undoubtedly has the 

 formula 



CMe.COOH 

 CMe.2 .CH, 

 CO / 

 CH, 



CMe.COOH 

 / \ 



or 



(Compare E. 



CMe., 



I 

 CH, 



\ / 

 CO 



CH., 



ii. and E. .3.) 



The only formula' which contain this complex, and conform to the 

 established conditions, are the Bredt, Perkin, and Perkin -Bouveault 

 formulse, namely 



CMe.CO 



/ CH, 

 CMeg I 

 \ CH-CHo 



CMe. CO 



CH, 



CMe 



CHo 



CH-CH.2 



Bredt. 



CHo 



Perkin.' 



CMe.CO 



CH-CH, 



CH, 



CH, 



Perkin-Bouveault., 



' Irans. Chem. Soc, 71, 11G9. 



- In Pel'kin's original paper, Trans. Chem. Soc, 73, 819, the position of the — CO- 

 and — CHj — group in the ketone ring is tho inverse of the abovei 



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