ALLYL ALCOHOL. 119 



The remaining hydrocarbons of this series Hepty- 

 lene C 7 H 14 , boiling point, 94-96 ; octylene C 8 H 16 , boiling 

 point, 118-120; nonylene C 9 H 18 , boiling point, 140; 

 decatylene C 10 H 20 , boiling point, 158-160 are obtained 

 in the same manner by treating the alcohol chlorides 

 or iodides with alcoholic potassa, or like diamylene 

 C 10 H 20 , boiling point, 150-153 ; dihexylene C 12 H 24 , and 

 triamylene C 15 H 30 , etc., by polymerisation of the simpler 

 hydrocarbons by means of sulphuric acid. 



B. MONATOMIC ALCOHOLS, C n H 2n O. 



The alcohols of this series bear the same relation to 

 the hydrocarbons of the ethylene series, as the alcohols 

 Qnjpn+2Q |. )ear O ^ e hydrocarbons of the marsh gas 

 series. There is at present but one alcohol belonging 

 to this group well known. 



Allyl Alcohol. 

 C 3 H 6 = CH 2 :CH.CH 2 .OH. 



Formation and preparation. Four parts glycerin are 

 heated slowly with one part crystallized oxalic acid 

 (an addition of quarter to half per cent, ammonium 

 chloride is advantageous) to 220-230, finally to 260. 

 At first an aqueous solution of formic acid passes over, 

 afterward allyl alcohol. The receiver is changed when 

 the temperature of the mixture has reached 195 ; 

 that which passes over from 195-260 is redistilled, 

 the operation being continued until potassium car 

 bonate precipitates no oil drops from a specimen of 

 the distillate. The allyl alcohol is then precipitated 

 from the whole distillate with potassium carbonate, 

 purified by treatment with powdered potassium hy 

 droxide, freed of water, by means of barium hydroxide, 

 and rectified. Or allyl iodide is transformed into allyl 

 oxalate by digestion with silver oxalate ; this is then 

 decomposed by means of dry ammonia gas and the 

 alcohol distilled oft . It is also produced by the action 

 of sodium on dichlorhydrine (see Glycerin). 



