252 PROCEEDINGS OF THE AMERICAN ACADEMY 



XVII. 



CONTRIBUTIONS FROM THE CHEMICAL LABORATORY OF 



HARVARD COLLEGE. 



TRIANILIDODINITROBENZOL AND CERTAIN 

 RELATED COMPOUNDS. 



By C. Loring Jackson and H. N. Herman. 



Presented November 9, 1892. 



In a paper * published last year by one of us and W. B. Bentley, 

 two forms of anilidotrinitropbenyltartronic ester were described, 

 one of which was red and melted at 143°, the other yellow with a 

 melting point of 122°. We have undertaken a more complete study 

 of this subject because the existence of these two modifications, if 

 they are really chemical isomeres, is not explained by any of the 

 present theories of isomerism, unless indeed this should prove to be 

 a case of an unsymmetrical nitrogen atom according to the hypothe- 

 sis proposed by Hantzsch and Werner, f The anilidotrinitrophenyl- 

 tartronic ester can be prepared in quantity only at a great expense 

 of time and labor. It seemed wise, therefore, to begin our work by 

 an examination of some related substances for similar modifications, 

 as, if such were discovered in the case of a more accessible com- 

 pound, their complete characterization could be worked out with 

 greater ease. Unfortunately, as the new modifications obtained 

 during these experiments were not so well marked as those already 

 found, they could not be used to advantage for this purpose, and 

 this work has taken so much time that the fuller study of the two 

 forms of anilidotrinitropbenyltartronic ester could not be entered 

 upon before the departure of one of us from Cambridge. The work 

 contained in this paper, therefore, relates principally to the triani- 

 lidodinitrobenzol, which we have found appears in both red and 

 yellow crystals, differing most strikingly in color and habit, but 

 melting apparently at the same temperature, and passing from one 



* These Proceedings, Vol. XXVI. p. 67. t Ber. d. ch. G., 1890, p. 11. 



