RvAN AM) Egax — Tht'. Aclioii of Nilrom Acid. cVc, on Urcthancs. 171 



2. jSTitvous fumes were passed for fifteen miimtes Lliroiigh a similar solu- 

 tion of diphenyluretliane in glacial acetic acid at the ordinary temperature. 

 The sohition was allowed to reuiaiu in a stoppered flaslv for two days, and 

 was tlien poured into water. The yellowish crystals which separated were 

 filtered, and recrystallised from methylated sp.'^jt. The purified substance 

 melted at 69° C, and a mixture of it with 4-nitro-diphenylurethane also 

 melted at this temperature. Under these conditions, tlierefore, nitrous fumes 

 converted the urethane into ^.-nilro-diphemylurdhane. 



In another experiment in- which nitrous fumes were passed into the solution, 

 cooled in ice for thirty minutes, the yellow oil which separated on pouring the 

 mixture into water, was recrystallised from alcohol and was then found to 

 consist mainly of 4--10 dinitro-diplu'nzylnrethanc. 



B. — Action of Nitrous Acid and Nitrous Fumes on Phcnyl-Bcnzyl Uthcr. 



(a) Nitrous acid. — 1. A five per cent, solution of phenyl-benzyl ether on 

 glacial acid, to which six molecular quantities of butyl nitrite had been added, 

 was allowed to remain in a stoppered flask at the ordinary' temperature for 

 three months. On evaporation of the butyl nitrite from the upper layer, which 

 separated on pouring the mixture into water, the oily residue solidified 

 after some time, and the product thus obtained, after recrystallisation from 

 methylated spirit, proved to be unchanged pJienylbcnzyl-ethcr. When the 

 lower aqueous layer was extracted with ether, the ethereal solution ga'Ne, on 

 evaporation at the room temperature, a small quantity of eolourlesfi crystal- 

 line matter melting at 104°-107° C, which was found not to consist of 4 uitro- 

 phenyl-benzyl ether, or 4-nitrophenol. "We had not sufficient of the substance 

 to establish its identity. 



2. In a similar experiment to the above, in which the ether was dissolved 

 in alcohol, the only product obtained after removal of the solvent was a 

 brown tarry substance. This was dissolved in most of the ordinary organic 

 solvents, but from none of the solutions could a crystalline substance be 

 isolated. 



3. Two and a half grams of pheuyl-beuzyl ether were dissolved in 50 grams 

 of carbon tetrachloride to which 6 molecular quantities of butyl nitrite and 

 8 molecular quantities of glacial acetic acid had been added. After three months 

 a very small quantity of colourless platy crystals had separated on the bottom 

 of the reaction flask. 



They melted at 99=-100°C., and dissohed in water, the solution giving a 

 white precipitate, with calcium chloride. 



The carbon tetrachloride solution was neutralised with barium carbonate, 

 and on evaporation of the fil trate red oily crystals were obtained. They melted 



K.I. A. MtOC, VOL. .\XSVI, SKCT. C. [ ■^ ^ .' 



