134 Scientific Proceedings, Royal Dublin Society. 



(b) III carbon tetrachloride. — In an experiment similar to the last, but in which 

 carbon tetrachloride was employed as tlie solvent, oxalic acid separated on tlie 

 walls of the flask, after a few days, in the form of long, colourless prisms. The 

 carbon tetrachloride solution was washed with water and distilled under reduced 

 pressure. The yellowish-red oily mixture which remained was dissolved in hot 

 alcohol, from which 4-nitro-plienyl-benzylurethane and a small amount of some- 

 what impure trinitro-phenyl-benzylurethane, melting at 107°-109° C, separated on 

 standing. The main portion obtained by concentration of the alcohol remained, 

 however, in the form of an oil. 



-&.— ACTION OF NITRIC ACID ON PIIENYL-BENZYLURETHANE. 



I. — In tlw Absence of Solvents. 



(1) Ten grams of phenyl-benzylurethane were placed in a flask Immersed in a 

 freezing mixture, and 7 c.c. of fuming nitric acid (sp. g. 1-52) were added slowly 

 to the urethane, the temperature of which was kept at - 5° C. The mixture was 

 then allowed to remain at the temperature of the room for two days. Some large 

 crystals of oxalic acid which had formed were isolated and identified. The 

 brown oily mixture was poured into a large volume of water, and the yellow oil 

 which was thus separated was redissolved in boiling alcohol. The oil which 

 separated from the alcohol on cooling became largely crystalline in the course of 

 a couple of months. After a few recrystallisations from alcohol, the substance 

 was obtained in the form of almost colourless platy prisms, which probably 

 belonged to the rhombic system, but had truncated angles. It melted at 70°- 

 71° C, and gave on analysis the following results: — 



0'2008 g. of the substance gave 1 6'5 c.c. of moist nitrogen at 12'5° C. and 757 mm., 



corresponding to N 9"7. 

 C,6H,604N, requires N 9'33. 



By boiling this substance with alcoholic potash it was converted into 4-nitro- 

 phenyl-benzylamine, which separated in the form of golden- yellow leafy crystals, 

 melting at 147°-148° 0. The substance, which melted at 70°-71° C, was therefore 

 4-nitro-phenyl-benzylurethane. 



4:-Nitro-plie.nyl-benzylurethane is readily soluble in ether, chloroform, carbon 

 tetrachloride, or nitrobenzene, is soluble in hot alcohol, and is moderately soluble 

 in petroleum ether. 



(2) Ten c.c. of phenyl-benzylurethane were added slowly to a mixture of 15 c.c. 

 of fuming nitric acid (sp. g. 1"5) and 15 c.c. of fuming sulphuric acid (20 p.c. SO3), 

 which was kept at - 10° 0. by immersion in a freezing mixture. After remaining 

 overnight, the wine-red, syrupy liquid was poured into a large volume of water, 

 and the light yellow, curdy solid thus obtained was recrystallised from glacial 

 acetic acid, from which about 3 g. of colourless platy crystals separated. These 

 crystals of a tetranitro-phenyl-benzylurethane, melted at J.26°-137° C, and gave 

 on analysis the following results : — 



0'1343 g. of the substance gave IS'6 c.c. of moist nitrogen at 15° C. and 759 mm., 



corresponding to N 16'2. 

 C,fiH„0,„Ns requires N 16-3. 



Tctranitro-phenyl-benzylm-ethanc is readily soluble in chloroform, is soluble 

 with more difficulty in hot alcohol or acetic acid, and is only slightly soluble in 

 ether. 



