120 PROCEEDINGS OF THE AMERICAN ACADEMY. 



two nitro groups, as we had expected from the results of previous experi- 

 ments, and that the bromdinitroresorcine diethylether melting at 184° 

 has the constitution (OCoH5)2l,5,Br3.(NOo)o2,4. It is an interesting 

 fact in this connection that an isomeric bromdinitroresorcine diethylether 

 (having the constitution (OCoIT6)2l,3,Bro,(N02)22,4), in which the bro- 

 mine is not in the ortho position to two nitro groups, gave no replace- 

 ment of the atom of bromine by hydrogen, but, when treated with sodic 

 ethylate, gave dinitropliloroglucine triethylether by the replacement of 

 the bromine by an ethoxy group. Beilstein, in the third edition of his 

 Handbuch, provisionally places the diethylether C6H2(OC2lT5)2(N02)2 

 melting at 133°, and the corresponding dimethylether C6H2(OCH3)2(N02)2 

 melting at 167°, prepared from tribromdinitrobenzol by W. H. Warren 

 and one of us,* under the adjacent dinitroresorcine. The determination 

 of the constitution of the diethylether just given necessitates their trans- 

 fer to the symmetrical dinitroresorcine, as there can be no question that 

 the methylether has the same structure as the ethyl compound. It also 

 shows tliat the dimethylether CgH2(OCII3)2(N02)2 melting at G7°, pre- 

 pared by Honigt by the direct action of nitric acid on a solution of re- 

 sorcine dimethylether in glacial acetic acid, cannot have the symmetrical 

 structure which Beilstein assigued to it, as this now belongs to the body 

 melting at 167°. 



In addition to this determination of the constitution of dinitroresorcine 

 diethylether, we have made a mi»re careful study of the products of the 

 reaction between sodic ethylate and tribromdinitrobenzol melting at 192° 

 both at ordinary temperatures and when aided by heat. These reactions 

 had been already studied by W. H. Warren and one of us, J with the result 

 that in the cold the bromdinitroresorcine diethylether melting at 184° 

 was formed, whereas, when hot, the dinitroresorcine diethylether melting 

 at 133° was the product isolated. As, however, subsequent work§ upon 

 the tribronitriniti'obenzol showed that in that case the action was far from 

 simple, it hardly seemed probable that the dinitro compound had given 

 only one organic product in each of thesfe cases, and this inference was 

 confirmed by our first new experiment m this field, as we found sodic 

 nitrite as well as sodic bromide among the products of the reaction, so 

 that it was evident that some other compounds were present besides those 

 recognized by Warren and one of us. The result of this later work was 



* These Proceedings, XXV. 170, 178. 



t Ber. d. chem. Ges., XI. 1041. 



J These Proceedings, XXV. 166. 



§ Jackson and Warren, Ibid., XXVII. 283. 



