291 PROCEEDINGS OF THE AMERICAN ACADEMY 



II. 0.1624 gr. of the substance gave, by the method of Carius, 

 0.0578 gr. of argentic bromide. 



Calculated for Found. 



C 6 Br(N0 2 ) 2 (C 6 H 6 NH) 3 . I. II. 



Nitrogen 13.46 13.81 



Bromine 15.38 15.15 



Properties. — Bromtrianilidodinitrobenzol forms a brilliant but rather 

 dark red crystalline powder, which, when examined with the micro- 

 scope, consists of crystals of two forms, rather short prisms terminated 

 by an obtuse angle, and thick groups shaped like an hour-glass and 

 made up of short prisms, which seem to have the same terminal angles 

 as those which are not in groups ; the groups are rather darker in 

 color than the free prisms, but this is probably due to their being 

 thicker. When crystallized from hot alcohol, instead of the usual 

 mixture of alcohol and chloroform, characteristic forms like sheaves 

 were obtained, also a small quantity of red nearly square plates. It 

 melts at 175°-176° ; is essentially insoluble in ligroine, or in water 

 either cold or boiling ; very slightly soluble in cold alcohol, more 

 soluble in hot ; more soluble in methyl than in ethyl alcohol ; slightly 

 soluble in cold ether, freely in hot ; moderately soluble in glacial acetic 

 acid ; freely soluble in benzol, chloroform, or carbonic disulphide ; 

 very freely in acetone. The best solvent for it is a mixture of alcohol 

 and chloroform, as it tends to separate in a viscous state from the 

 solution in chloroform alone. Strong sulphuric acid dissolves it 

 slightly, forming a pale yellow solution. Strong nitric acid acts in the 

 same way, but less energetically ; fuming nitric acid acts upon it vio- 

 lently even in the cold. Hydrochloric acid has no action either hot 

 or cold. The absence of basic properties is accounted for by the 

 presence of the two nitro groups. We tried also the action of sodic 

 hydrate, as certain nitroamido compounds possess weak acid proper- 

 ties, — for instance, the trinitrotoluidine of Nblting and Salis,* — but 

 found that it produced no effect. 



Dibromdinitrophenylmalonic Ester, C c HBr 2 (N0 2 ) 2 CH(COOC 2 H 5 ) 2 . 



This substance was prepared by acting on one molecule of tetra- 

 bromdinitrobenzol with about four molecules of sodium malouic ester, 

 as follows : 15 grs. of tetrabromdinitrobenzol dissolved in about 20- 

 30 c.c. of benzol were mixed with 20 grs. of malonic ester previously 

 converted into sodium malonic ester by treatment with the sodic ethyl- 



* Ber. d. ch. G., xv. 18G4. 



