CONTRIBUTIONS FROM THE CHEMICAL LABORATORY OF 

 HARVARD COLLEGE. 



ON CERTAIN DERIVATIVES OF SYMMETRICAL 

 TRICHLORBENZOL. 



By C. Loring Jackson and F. H. Gazzolo. 



Presented October 12, 1898. Received October 20, 1898. 



In a paper by Sidney Calvert and one of ns,* the behavior of tri- 

 bromiodbenzol Br3l,3,5,r2, and of tetrabrombeuzol Br4l,2,3,5, with 

 sodic ethylate was studied, and it was shown that the atom of iodine 

 (or the atom of bromine in the corresponding position) was replaced by 

 hydrogen under these conditions, giving the symmetrical trihroml^enzol. 

 It seemed of interest in this connection to study the corres[)onding tri- 

 chlor compounds, that is, the trichloriodbenzol and the trichlorbrorabenzol, 

 to see whether the loosening effect of the three chlorine atoms might 

 not be even greater than that of the three atoms of bromine, and thus 

 make it possible that these substances would react with other. agents 

 beside sodic alcoholates, which were the*only reagents that had any such 

 effect upon the bromine compounds. 



At that time it was not worth while to undertake tlie work, because of 

 the great difficulty in preparing symmetrical trichloraniline, but since 

 this obstacle has been removed by the beautiful method of Victor Meyer 

 and Siidborough,t we have prepared these compounds and studied some 

 of their relations. Trichloriodbenzol, Cl3l,3,o,I2 melts at 55°; and by 

 treatment with sodic elhylate dissolved in alcohol and benzol yielded 

 symmetrical tricldorbeuzol recognized by its melting point 04° and two 

 analyses. It therefore behaved like the tribromiodbenzol under these 

 conditions. All our other attempts to obtain a simple replacement of 

 the iodine in this substance failed, so that it is no more reactive than the 

 tribromiodbenzol. Fuming nitric acid converted the trichloriodbenzol 

 into the trichlordinitrobeuzul melting at 129°, iodine being set free. 



* These Proceedings, XXXI. 123. 

 t Ber. d. chem. Ges., XXVII. 315L 



