314 



EEPOET— 1900, 



converted into oxalic acid and camphouonio acid (compare E. 2. a li.), all 

 action which apparently must be expressed as follows : 



C=CH . COOH 



CO + COOH. COOH 



0H„ 



CH., 



CMe., 



CMt 



CH2 



CH, 



or 



C . COOH 

 Me 



.C=CH . COOH 



^ C . COOH 

 Me 



.CO + COOH. COOH 



CH, 



I CH, 

 CMe2 



CH, 

 -> I CH, 

 CMea 



c . coon 



Me 



C . COOH 1 

 Me 



i. I^ORMATION AND PROPERTIES OF THE CaMPHOLENIC DERIVATIVES. 



The isomeric substances n- and /3-campholenic acids are obtained in 

 several ways, the most important of these being the dehydration of cam- 

 phoroxine by various methods, when their nitriJes are produced in large 

 quantities : 



C,„H„:N.0H=C,,H,5 .CN + H2O. 



Interesting, also, is the fact that u-campholenic acid is found amongst 

 the products obtained by the action of sodium amalgam on /3-dibromo- 

 camphor. 



C,oH,,Br,0 + 2H + H20=C,,H|, . COOH + 2HBr. 



The campholenio acids are undoubtedly both unsaturated monobasic 

 acids containing one closed carbon f;hain. The o-acid is optically active, 

 whilst the /3-acid and all its derivatives ai-e quite inactive ; so that both 

 the asymmetric carbon atoms of camphor have been involved in the change 

 whereby this substance is produced. Both the «- and the /3-acids have the 

 double or ethylenic linking at the y- or t-pusition, as both are readily 

 converted into lactones when treated with dilute acids. 



a-Campholenic acid may be converted into /3-campholenic acid by several 

 processes, and invariably becomes inactive during the process. It would 

 appear from this that /3-campholenic acid is a secondary product of 

 change. 



Each acid, on oxidation with potassium permanganate, is converted 

 into a dihydroxydihydrocampholenic acid by addition of the elements of 

 hydrogen peroxide in the usual way. When these dihydroxy acids are 

 distilled they are converted by loss of water into new substances, pre- 

 sumably ketonic acids, the a -acids affording pinonic acid, which is an 

 oxidation product of pinene. 



Lapworth, Trans. Chcm. Sue, 11. 105G. 



