204- Dr. Hofniann on Chloranil. 



the chlorophenussic acid C,2 Cl5O + HO = 66*50 per ct. chlo- 

 rine. 



In this way a Large quantity of chhirophenissic acid may 

 be readily obtained as an accompanying product in the pre- 

 paration of chloranil. 



From the foregoing it is seen that the chlorophenissic acid 

 can be transformed into chloranil, of which fact I have 

 also convinced myself by direct experiment. It occurred to 

 me to endeavour to produce chloranil from other members o\ 

 the phenyle series. By a longer or shorter action of nitric 

 acid upon hydrate of phenyle, Laurent converted it into nitro- 

 phenessic and nitrophenissic ncids (carbazotic acid). These 

 two acids, when treated with hydrochloric acid and chlorate 

 of potash, yield chloranil with the greatest facility. When 

 nitrophenessic acid is taken, alcohol should be employed, on 

 account of its insolubility in water. 



Schunck* obtained some years ago, in treating aloes with 

 nitric acid, an acid (chrysolepinic) having the same compo- 

 sition and the greatest similarity with carbazotic acid, but 

 which was said to be different on account of some devintions 

 in its compounds. It was therefore the more interesting to 

 produce chloranil from this body, as Marchandf has asserted 

 lately that the carbazotic and the chrysolepinic acids are 

 identical. The chrysolepinic acid is indeed transformed into 

 chloranil. I have repeated this experiment several times with 

 complete success, as well with a product which I prepared as 

 with a specimen which Schunck iiad left in the collection of 

 Professor Liebig. 



The new researches of Gerhardt;]: and Cahours§ have shown 

 so close a connection between the compounds of phenyle and 

 those of salicyle, that the conversion of the latter into chlora- 

 nil was to be expected. To produce this metamorphosis, it is 

 indeed only necessary to boil salicylous acid (salicide of hy- 

 drogen), salicylic acid, or nitrosalicylic acid (indigotic or anilic 

 acid), with hydrochloric acid and chlorate of potash. The 

 decomposition in all these cases is very simple, the superfluous 

 carbon escaping in the form of carbonic acid, e.g. 



C14H5O3 + HO + lOCi + 40= C,oCl404+ 2CO2 + CHCl. 



' -V ' V_^^ , 



Salicylous acid. Chloranil. 



Although it is known that benzoic acid and salicylous acid 

 are identical, still the former, when treated as above, does not 



* Liebig's .'Inn,, Bd. xxxix. S. 7. 



t Journ.fdr Prakt. Cliem,, Bd. xxxii. S. 3o. 



I Liebig's Ann,, Bd. xlv. S. 19. 



\ Ann, de Chim. ei de Phys., Sme S. t. x. p. 327. 



