264 PROCEEDINGS OF THE AMERICAN ACADEMY. 



C6H3(N02)n[CHNa(COOC2H5)o]3. The formation of compounds with 

 three molecules of the sodium constituent is noteworthy, since all the 

 compounds analyzed heretofore have contained the two constituents in 

 the proportion of one molecule of each. Similar experiments with sodic 

 methylate, ethylate, or amylate and trinitrobenzol also led to products 

 apparently containing three molecules of the alcoholate to each molecule 

 of the nitro compound * — a surprising result, since Lobry de Bruyn and 

 Van Leent f obtained from trinitrobenzol a substance with the following 

 formula, C6H3(N02)3KOCH3|^H20. The difference in the results is un- 

 questionably due to differences in the method of preparation. Lobry de 

 Bruyn and Van Leent's compound was obtained by crystallization, 

 whereas all our products with three molecules of the alkaline material 

 were precipitated from an alcoholic solution with benzol. Experiments 

 are now in progress to test this explanation of the phenomena. 



The discovery of these sodic malonic or acetacetic comjiounds would 

 furnish a strong argument, if that were needed, against the only theory 

 for these colored substances as yet published, — that of Victor Meyer, t 

 who supposed they were formed b}' the replacement of atoms of hydro- 

 gen on the benzol ring by atoms of sodium. This theory has been dis- 

 proved by the observations of Lobry de Bruyn, § supported by those 

 made in this Laboratory ; || and among other arguments the point was 

 made that Victor Meyer's theory necessitated the assumption of alcohol 

 of crystallization in every compound of this class which had been ana- 

 lyzed. In these malonic and acetacetic compounds the presence of malonic 

 ester or acetacetic ester of crystallization must be assumed, if this theory 

 is adopted ; and, further, the number of molecules of " ester of crystalli- 

 zation " corresponds in each case to the number of atoms of sodium ; the 

 view, therefoie, that the colored bodies are addition and not substitution 

 compounds is confirmed by these observations. 



Other experiments were tried to study the effect on the formation of 

 the colors of increasing or diminishing the negative nature of the aromatic 

 constituent. That there is some effect of this sort has been shown already, 



* The ethyl and methyl compounds seemed to contain alcohol of crystallization, 

 to judge from the percentages of sodium obtained. The publication of these results 

 will, therefore, be postponed until further analytical data have been collected. The 

 amyl compound, on the other hand, gave a percentage of sodium corresponding 



to C6H3(N02)3(Na005Hu)8- 



t Rec. Trav. Chira. Pay.s-Bas, XIV. 150. 

 t Ber. d. chem. Ges., XXVII. 3153. 

 § Rec. Trav. Chim. Pays-Bas, XIV. 89. 

 II These Proceedings, XXXIII. 174. 



