JACKSON, DUNLAP. — BROMINE DERIVATIVES OP RESORCINE. 239 



days, the residual oil turned rather viscous, and crystals were seen 

 permeating the mass. These crystals may be obtained by absorbing 

 the oil with bibulous paper or by distilling in vacuo. By crystalliza- 

 tion from dilute alcohol the constant melting point 76° was obtained, 

 and as the crystals are white, contain no bromine, and their solu- 

 bility, mode of crystallization, and shape correspond with those of 

 acetyleutetracarboxylic ester, there can be no doubt that they are 

 this substance. This acetyleutetracarboxylic ester could hardly have 

 been formed otherwise than by the action of brommalonic ester on 

 sodiummalonic ester, and the brommalonic ester it would seem must 

 have been produced by the interchange of a bromine atom of the tri- 

 bromresorcine with one of the atoms of hydrogen of the malonic ester. 

 It follows from this reasoning, therefore, that we have here another 

 case of the curious replacement of bromine by hydrogen, so often 

 observed in this Laboratory, and that the two hydroxyl groups of the 

 resorcine exercise the same action on one or more of the atoms of 

 bromine as the two nitro groups in the tribromdinitrobeuzol. The 

 following fruitless attempt was made to isolate the other organic de- 

 rivative formed. If the red oil absorbed by the bibulous paper, after 

 the acetyleutetracarboxylic ester has been separated as completely as 

 possible, be treated with benzol, it is divided into a soluble and an 

 insoluble portion. The insoluble portion, by precipitating an alcoholic 

 solution of it with benzol, came down in a flocculent form, and when 

 dry was light brick-red in color. It was evidently closely related to 

 the substance obtained by the action of water or sodic carbonate on 

 the tribromresorcine, and like that could not be purified. 



Action of Nitric Acid on Tribromresorcine . 



Fuming nitric acid reacts easily with tribromresorcine. The product 

 was recrystallized from benzol and upon analysis gave the following 

 results : — 



0.2219 gram of the substance gave by the method of Carius 0.1479 

 gram of argentic bromide. 



Calculated for 

 C 6 HBr(N0 2 ) 2 (0H) 2 . Found. 



Bromine 28.67 28.37 



This analysis and its melting point, 192°-193°, show it to be the 

 body heretofore described by Typke * and Fevre.f 



* Ber. d. ch. G., XVI. 555. 



t Bull. Chem. Soc, XXXIX. 591. 



