JACKSON AND PHINNEY. PICRYLMALONIC ESTER. 115 



ation, which disappears from the solutions, as the substituted toluol is 

 purified by recrystallizatiou. The solvents which follow dissolve the tri- 

 nitrophenylacetic acid without decomposition ; easily soluble in ether, 

 glacial acetic acid, acetone, or ligroine ; soluble in chloroform, less so in 

 benzol or carbonic disulphide. The best solvent for it is benzol. The 

 three strong acids seem to dissolve it without decomposition; it is more 

 soluble in nitric acid or sulphuric acid than in hydrochloric acid. Alka- 

 lies dissolve it easily, forming deep blood-red solutions of its salts, but we 

 have not yet succeeded in bringing any of these salts into a state fit for 

 analysis. 



Attempts to Make Ditrinitrophenylmalonic Ester. 



Dittrich,* in his work on the action of picrylchloride on sodium aceta- 

 cetic ester, obtained without ditficulty a ditrinitrophenylacetacetic ester ; 

 in fact this substance occurred as a secondary product in his preparations 

 of trinitrophenylacetacetic ester, when he used the reagents in molecular 

 proportions. It seems strange, therefore, that we have never observed 

 the formation of a ditrinitrophenylmalonic ester as a secondary product 

 in any of our preparations of the mono substituted ester. In the hope 

 of preparing this substance (ditrinitrophenylmalonic ester) we converted 

 5 grams of the trinitrophenylmalonic ester into its sodium salt by treat- 

 ment with the sodic ethylate from 0.31 gram of so<lium, and then treated 

 it with 3.4 grams of picrylchloride. The mixture was allowed to stand 

 at ordinary temperatures over night, and, as no apparent chanjie had 

 taken place, it was divided into two portions, one of which was heated 

 on the steam bath until it turned brown, and the other allowed to stand 

 two weeks, when it had also turned brown, and deposited crystals of 

 sodic chloride. The brown solutions, whether obtained by heating or by 

 standing, yielded sodic picrate and a brown viscous mass, from which 

 nothing fit for analysis could be isolated. A repetition of the experiment 

 under other conditions gave the same result. It seems, therefore, that 

 picrylchloride brings about a deep seated decomposition, when it acts on 

 the sodium salt of the trinitrophenylmalonic ester, as the ditrinitrophe- 

 nylmalonic ester would be without doubt a well crystallized compound. 

 The products of this reaction recall Dittrich's description of the substances 

 obtained by him from the action of picrylchloride on sodium malonic 

 ester (pikrinsaures Natrium neben schmierigen Zersetzungs-producten des 

 Malonsaureester), and it may be that the presence of an excess of picryl- 



* Ber. d. chem. Ges., XXIII. 2720. 



