306 



Scientific Proceedings, Roi/al Dublin Society. 



point (86° C.) and other properties with the 2-nitrodiphenylethyleneether of 

 Weddige [loc. cit.). On tlie other hand, from 2-nitrophenol we obtained 

 2-nitrodiphenylethyleneether, which melted at 97° C. Owing to the discrepancy 

 between our results and those of Weddige, the preparation of the ortho compound 

 was repeated, using carefully purified materials, but the product again melted 

 at 97° C. 



Weddige 's results with regard to the 2-8- and the 4-10-dinitro compounds 

 we were able to confirm. 



The asymmetrical 2-10-dinitro derivative, which has not been previously 

 described, we prepared in an analogous manner from 2-nitrophenylbromethyl- 

 ether and potassium ^^-nitrophenol. 



By the action of nitric acid on the 2-8-dinitro derivative we obtained, in 

 addition to a tetranitro derivative, a trinitro compound, melting at 172° C, 

 and which was therefore very probably 2-4'8-trinitrodiphenylethyleneether. As 

 the same tetranitro derivative was obtained by the nitration of 410-dinitro- 

 diphenylethyleneether, its nitro radicles must be in the positions 2-4-810, and 

 the substance w"hich melted at 214° C. is therefore 2-4-8-10-tetranitrodiphenyl- 

 ethyleneether. Attempts to convert the tetranitro compound into a higher 

 nitro derivative by further nitration were unsuccessful, portion of the substance 

 being decomposed with formation of 2-4-dinitrophenol, but the greater part 

 of it being recovered unchanged. 



In acetic acid solution, at low concentrations of the solutes and at the 

 ordinary temperature, nitric acid, even on prolonged standing (10 weeks), 

 did not nitrate the ether. Under similar conditions we obtained from carbon 

 tetrachloride solutions of the interacting sabstances 410-dinitrodiphenylethylene- 

 ether, 2-4-8-10-tetranitrodiphenylethyleneether, oxalic acid, and 2-4-dinitro- 

 phenol. 



Nitrogen peroxide in the vapour phase or in solution converted the ether 

 into 4-10-dinitrodiphenylethyleneether. In the former case a small quantity 

 of a substance which exploded violently at 203° C. was obtained, and in the 

 latter case, in addition to the dinitro compound, we also isolated some 2-4-dinitro- 

 phenol. 



The course of the nitration of the original ether and its nitro derivatives 

 may be conveniently illustrated by the following diagram : — 



2-Nitrodiphenylethvleneethei- 

 (M.P. 97° C.) 



! I 

 1 I 



Diplienyletliyleneether 

 (M.P. 97° C.) 



2-8-Diniti-o(iiphenylethTleTieetlier 

 (M.P. 168° C!) 



4-Niti-odipheiiylethyleneether 



(M.P.'86°C.) 



I 

 I 



si/ i 



4-10 -Dinitrodiphenvlethyleneether 

 (M.P. 143° C") 



\ ^ 



*> ■ 4 ■ S-Trinitrofiiphenylethyleneetliei- 

 (M.P. 172° C.) 



y \^ \|' N' -^ 



2"4'8-10-Tetraniti-odiphenylethyleneether 

 I (M.P. 214° C.) 



2-4-Diaitrophenol -I- oxalic acid. 



