120 
MR. C. SCHORLEMMER ON THE NORMAL PARAEEINS. 
of hexane, besides smaller quantities of hexene and a higher boiling liquid. The latter 
compound is a dihexyl , C 12 H 26 ; it boils at 201°, and has at 17° the specific gravity 0-7738. 
It has the same boiling-point as the dihexyl obtained by the electrolysis of cenanthylic 
acid, which, as I shall show further on, is also a normal hydrocarbon. Whether these 
two hydrocarbons are identical or not has to be yet decided. The dihexyl from mannite 
might possibly have the following constitution : — 
C 4 H 9 
C Hoj 
IcH — 
CH 
c 4 h 9 
CH, ' 
By acting with zinc and hydrochloric acid upon hexyl iodide the following is the 
principal reaction : — 
c 6 h 13 i+h 2 =c 6 h 14 +hi. 
But besides that also the following decompositions occur : — 
2C 6 H 13 I+Zn=C 6 H 14 + C 6 H 12 +Zu I 2 . 
2C 6 H 13 I+Zn=C l2 H 26 +ZnI 2 . 
Normal Dipropyl, C 6 Ii 14 . 
To obtain this compound, allyl alcohol was first prepared from glycerine by Tollen’s 
method * and converted into propyl alcoholf , from which propyl iodide was obtained, 
boiling at 100° to 102°. On adding anhydrous ether and sodium to this iodide no 
reaction took place, either at the ordinary temperature or at the boiling-point of the 
mixture. To effect a complete decomposition, the substances had to be heated together 
in closed tubes to 140°-150°. 
Pure dipropyl boils at 69° to 71°, and has at 17° the specific gravity 0-6630. It has, 
therefore, the same physical properties as the hexane from mannite, and from its for- 
mation it follows that it has also the same constitution. The quantity obtained was 
not sufficient to examine its derivatives. 
Normal Heptyl Hydride , or Heptane , C 7 II 16 . 
This hydrocarbon was first discovered by me in the light oils from cannel coal-tar^, 
and afterwards I found it in large quantities in the petroleum from Pennsylvania §. 
Warren has since shown that, besides this body, petroleum also contains an isomeric 
heptane, which boils at 90 u -4 || ; and my later researches have led me to the same con- 
clusion^]". This lower-boiling heptane is always present, but in smaller quantities than 
the normal hydrocarbon. As the boiling-points of the two isomerides differ only by 10°, 
their complete separation is a very difficult and tedious process. By a very carefully 
* Ann. Chem. Pharm. vol. clvi. p. 104. t Ibid. vol. clis. p. 92. 
+ Chem. Soc. Journ. vol. xv. p. 419. § Chem. Soe. Journ. [2] vol. i. p. 216. 
|| Chem. News, vol. xiii. p. 74, from Mem. Amer. Academy. Proc. Roy. Soc. vol. xiv. p. 468. 
