144 PROCEEDINGS OF THE AMERICAN ACADEMY. 



when it showed the melting point 129°, and is therefore the trichlor- 

 diuitrobenzol Cl3l,3,o,(iS02)22,4. 



Trichlorhrombenzol CgHjClsBr. 



Twenty grams of trichloraniline dissolved in 100 c.c. of hot glacial 

 acetic acid were mixed with 90 c.c. of hydrobromic acid (boiling at 125°), 

 and, disregarding the heavy grayish yellow precipitate, the mixture was 

 thoroughly cooled in an ice bath, and then treated with powdered sodic 

 nitrite, until red fumes were given off freely. The sodic nitrite was 

 added in small quantities at a time, and the flask containing the mixture 

 shaken vigorously after each addition, the liquid behig kept cool through- 

 out. The heavy precipitate already mentioned went into solution during 

 the addition of the sodic nitrite, forming a dirty yellow liquid. After 

 standing for a few hours to complete the reaction, the contents of the 

 flask were poured into an evaporating dish, and heated for an hour on 

 the steam bath. In this way a dark oily product floating on the surface 

 of the liquid was obtained, which solidified on cooling. The mother 

 liquor deposited more of this product in a semi-crystalline condition, and 

 an additional amount was obtained from it by heating it again with more 

 hydrobromic acid. The product was purified by sublimation followed by 

 recrystallization from alcohol, until it showed the constant melting point 

 64°_65°. As this is the same as the melting point of trichlorbenzol, we 

 supposed at first that our product was this body, but the following analy- 

 ses of the substance dried in vacuo showed that it was the desired 

 trichlorhrombenzol. 



I. 0.1618 gram of the substance gave by the method of Carius 0.3850 



gram of the mixture of argentic chloride and bromide. 

 II. 0.1116 gram of the substance gave 0.2656 gram of the mixture of 



argentic chloride and bromide. 

 III. 0.1276 gram of the substance gave on combustion 0.1274 gram of 



carbonic dioxide and 0.0108 gram of water. 



* By a curious coincidence the results of analyses I. and II., if calculated 

 as argentic chloride, give numbers agreeing excellently with the percentages calcu- 

 lated for CfiHgClg, so that the combustion was necessary to determine whether our 

 compound was this, or the CeHgClsBr which has the same melting point. 



