OF ARTS AND SCIENCES. ' 277 



The broraacetacetic ester being afterward attacked either by a 

 molecule of sodium acetacetic ester or by sodic hydrate. 



The only question with regard to these reactions, which might arise 

 would be due to the fact that only a little over 50 per cent (59 per 

 cent) of the ester was obtained, which might lead to the hypothesis 

 that nearly half of the tribromdinitrobeuzol went to form another 

 substance ; but this objection is removed by the fact that in another 

 analogous case as much as 80 per cent of a corresponding ester has 

 been found. We consider, therefore, that the missing 41 per cent of 

 the ester remained dissolved in the oily secondary product, but should 

 state, on the other hand, that upon treating the oil with sulphuric acid 

 of specific gravity 1.44 in hopes of decomposing the secondary products 

 and converting the bromdinitrophenylacetacetic ester into bromdinitro- 

 benzylmethylketone, we obtained nothing but black tarry substances, 

 from which no substance fit for analysis could be obtained. 



Properties. — The bromdinitrophenylacetacetic ester crystallizes 

 well, usually in forms looking like a rhombohedron with a very acute 

 angle, less frequently in prismatic forms, which are twinned on a cen- 

 tral line parallel to their longer axis, the termination being in shape 

 either like a simple gable, or one with a notch in its point. The crys- 

 tals show a great tendency to twin, or group, often in forms like 

 those of frost, and are sometimes from 2 to 3 mm. long. The sub- 

 stance has a yellow color of about the shade of potassic chromate, 

 which is characteristic, as the corresponding malonic compound is 

 nearly white. Heckmann * has observed a similar deep yellow color 

 in the orthoparadinitrophenylacetacetic ester. It melts at 9G° ; is very 

 slightly soluble in water, rather more so in hot than in cold ; essen- 

 tially insoluble in ligroine ; not very soluble in cold alcohol, but freely 

 in hot ; if anything less soluble in methyl than in common alcohol both 

 cold and hot, but the solubility is much greater in the hot methyl alco- 

 hol than in the same solvent when cold ; tolerably soluble in carbonic 

 disulphide, or ether; soluble in glacial acetic acid; and freely in ben- 

 zol, chloroform, or acetone ; from ether, benzol, or chloroform it is 

 deposited as an oil. The best solvent for it is hot alcohol. Strong 

 sulphuric acid does not act upon it in the cold, but when warm dia 

 solves it, forming a slightly yellowish solution. Strong hydrochloric 

 acid has no action with it in open vessels, even if heated. The de- 

 composition of the substance by these two acids under proper condi- 

 tions is described later in this paper. Strong nitric acid has no action 



* Ann < hem., ccxx. 133. 



