23, 3 West and Balce: Composition of Pili-nut Oil 273 



temperature of —10° and bromine was added slowly, after 

 which the solution was allowed to stand about three hours at 

 —10°. No crystals of linolenic hexabromide, which is insoluble 

 in ether, were obtained. This indicated that pili-nut oil con- 

 tained no linolenic glyceride. The ethereal solution was then 

 treated with 10 per cent sodium thiosulphate solution, to remove 

 the excess of bromine. This treatment was repeated, to remove 

 the last traces of bromine, after which the separated ethereal 

 solution was dehydrated with anhydrous sodium sulphate, filtered, 

 and distilled to eliminate the ether. The residue was then 

 treated with petroleum ether (boiling point, 35° to 55°) and 

 heated (reflux) for about a half hour. The petroleum ether 

 solution was then cooled and allowed to stand several hours. 

 No crystals of linolic tetrabromide were obtained. The solu- 

 tion was concentrated, by distilling, to a volume of about 200 

 cubic centimeters, cooled, and allowed to stand several hours, 

 but still the tetrabromide did not crystallize. This indicated 

 that, if the oil contained linolic glyceride, the percentage was 

 probably small. The petroleum ether solution was concentrated 

 to a volume of about 100 cubic centimeters, transferred to a 

 small distilling flask, and the petroleum ether eliminated by 

 distilling under diminished pressure. The dry residue (3.3540 

 grams) was weighed and the bromine content determined by 

 boiling about 0.1 gram with about 0.5 gram of solid silver 

 nitrate and 30 cubic centimeters of pure concentrated nitric 

 acid. The precipitated silver bromide was then collected on a 

 Gooch filter. The bromine content of the residue was found to 

 be 36.03 per cent. Since oleic dibromide contains 36.18 per 

 cent bromine the unsaturated acids consist entirely of oleic acid. 

 The unsaturated acids separated by the lead-salt method and 

 corrected for the unsaturated acids, which were present as im- 

 purity in the impure saturated acids, amounted to 57.21 per 

 cent (Table 2) . This is equivalent to 59.78 per cent of oleic gly- 

 ceride which, according to the analysis, is the only unsaturated 

 glyceride present in the oil. 



Since the unsaponifiable matter (0.19 per cent, Table 1) pres- 

 ent in the oil goes with the unsaturated acids in the lead-salt 

 separation, the percentage of oleic glyceride corrected for un- 

 saponifiable matter is 59.78 - 0.19, or 59.59. 



The data obtained by analyzing the bromo-denvatives of the 

 unsaturated acids are given in Table 3. 



