BENZYL PHOSPHINES AND THEIR DERIVATIVES. 569 



were mixed with 70 c.c. of absolutely dry ether.* 22 grms. of pure iodide of benzyl 

 were dissolved in 150 c.c. of dry ether, and the two solutions mixed. A colourless 

 liquid resulted, which, with the exception of growing slightly turbid, did not suffer any 

 noticeable change after twenty-four hours. 



The ether was therefore distilled off. When most of it had passed over, the viscous 

 residue began to crystallise rapidly, and a brisk action appeared to occur, a considerable 

 quantity of hydriodic acid coming off. The flask was removed from the water-bath in 

 which it had been heated, and when cold a quantity of dry ether was added to its contents, 

 which consisted partly of crystalline matter, but chiefly of a brown viscous mass. The 

 latter, in contact with the ether, gradually became white and crystalline, eventually 

 completely so. This crystalline product was pounded up, and carefully washed with 

 dry ether. 



Some of the product thus purified was boiled with water, and yielded an oily liquid, 

 which on cooling partly solidified. This was treated with ether, when a white crystalline 

 solid remained, and on crystallising it from alcohol it had the characteristic form of 

 iodide of tetrabenzyl phosphonium. The whole of the product was treated with water and 

 steam in a current of hydrogen to decompose the hydriodates and to liberate the phos- 

 phines. No primary phosphine passed over. The water when cold was poured off, 

 and the semisolid mass again steamed with fresh water, and this poured off when cold. 

 Next the mass was shaken with ether and the solution filtered from undissolved crystal- 

 line matter. The latter, on recrystallisation, had the characteristic form of oxide of 

 tribenzyl phosphine. 



The ethereal solution on keeping deposited a good deal of crystalline matter. After 

 a day or two it was decanted from this, and boiled to dryness in a stream of 

 hydrogen. A colourless liquid remained, which gradually deposited crystals. The whole 

 was distilled in vacuo, the distilling flask being immersed in a fusible metal bath. 

 Pressure about 190 mm.; temperature of metal bath, 260°-270°. A fair quantity of liquid 

 distilled, its vapour having a temperature during distillation of 120°-125°. The residue 

 decomposed somewhat. (We discuss the properties of this distillate on p. 570.) 



Experiment 3. — 22 grms. of crystallised iodide of benzyl were placed in a flask full 



of carbonic anhydride, and 12 grms. of the primary phosphine (boiling point 170°-190°) 



added. The iodide of benzyl dissolved on agitation, then action gradually set in, and after 



some hours the mixture became solid. After about twenty-four hours, some of the solid 



product was removed, pounded up in a mortar, and washed six times by decantation 



with dry ether, until a drop of the washings left no appreciable residue on evaporation. 



It was then placed in vacuo, and formed when dry a colourless powder. 



Analysis. 



0-4428 gave 03032 Agl =0163857 1 = 3700 per cent. 



Obtained. Calculated for (C 7 H 7 ) 3 PH.HI 



Iodine, . . . 370 3713 



* Distilled from phosphoric anhydride. 



