170 PROCEEDINGS OP THE AMERICAN ACADEMY 



The more fusible portion of the secondary product, which had been 

 absorbed by the papers in the process of liquation, was extracted with 

 alcohol, and the oil thus obtained allowed to stand until it had nearly 

 solidified again, when it was submitted to a second liquation, the more 

 fusible product of which did not solidify, but only deposited a few 

 crystals. As there were only about 10 gr. of this in all, and it mani- 

 festly contained two, and in all probability three or more substances 

 we thought there would be little chance of isolating a pure compound 

 from it, and accordingly, after one or two attempts to separate it into 

 its components, its further study was abandoned. 



Action of Sodic Ethylate on Tribromdinltrohenzol with the Aid of 



Heat. 



As has been shown in the preceding section, sodic ethylate acting on 

 tribromdinitrobenzol (melting point 192°) in the cold converts it into 

 bromdiuitroresorciue diethylether melting at 184° ; but if, instead, the 

 two substances are heated together, a different product is obtained 

 which we have found it most convenient to prepare in the following 

 way. 



A solution of 10 gr. of tribromdinitrobenzol (melting point 192°) 

 in 20 c.c. of benzol was mixed with the alcoholic solution of sodic 

 ethylate formed from 45 c.c. of alcohol and 1.7 gr. of sodium, giving 

 the proportion of three molecules of the ethylate to one of the tri- 

 bromdinitrobenzol, and the mixture was heated on the steam bath to 

 gentle boiling for about ten minutes in a flask under a return con- 

 denser. Longer or more violent heating should be avoided, as in this 

 case a decomposition sets in, probably due to the action of the sodic 

 ethylate on the nitro groups, which increases the difficulty in purifying 

 the product. During the boiling the red color of the solution steadily 

 increased in intensity, and a considerable amount of sodic bromide 

 was deposited together with a brown amorphous substance which 

 added to the turbidity of the reddish brown liquid finally obtained. 

 A curious odor was also observed in the solution, which seemed to be 

 characteristic of all the reactions in which bromine was replaced by 

 hydrogen, and was probably due to the secondary product formed 

 from the sodic ethylate, but did not smell like the aldehyd which we 

 had supposed would be this secondary product by the following 

 reaction : — 



CgH.ONa + C6HBr(C.,H50)2(NO,), = 



NaBr+C,H;(C,H6O)2(NO02 +C,II,0. 



