22
HEPTYT.ENE FROM I1EPTAK;E O F 1’. S A R I N I A N A .
VI. HEI’TYLENE FRORI IIEPTrlNE OF P. SABINIANA. I ~ YI1‘. 1’. VE;SAI:I.IC, 1’11. L). I.iiitcr&ty o f S n r r i i
~‘iirc~liti,i
In a note on certain hc:IJtylic,derivntivcs piililished i n ISW“, mention was made of a hcptylcwe agreeing i l l hoilirig point with the one prepared by Scliorlerurrier fruni tile petl.oleuni-lie~)taric. This heytylene w : observcd ~ as onc of tlic: products i n prepariiig several of the heptylic tleriv:\tir from tlic brmiiile, but the method adopted for its sl)ecial 1)reparation \vas the action of Sodium ethylate upon the hc.ptylic broinitlc a t the tcrnlieratnre of boiling. T h e liquid o1)taiiicc.l was light, nio1,ilc n n ( l with a high rcfractive-index, . ! , pusscihirig ;L pleasant aromatic smell. Its boiling a t W - ~ ~ O C :ind specitic gravity m a s O . T O O T j (21”. 6 C‘). If sodium cthylnte is allowe(1 to act i l l the cold, a heptyletliylether is formed, togetlier with a small ; m o u n t of heptylene. Even when an exce-s of tlic sotlirini et1igl:itc is present, it is difIicult to change d l uf tile 1ii.oniiile to the etlicr. Analyses, however, of the heavy oily liquid obtained sliowcd the conversion to be almost complete H E P T Y L E S E UIZOJIIDE.
T h e action of bromine upon tlie heptane is slow, and heat must be applied. On the heptylene, broniine acts with great energy, heat being evolved. I n the first case, tlie resulting product is one of substitution; in the latter, it is one of acldi~iori;but substitution products are ~ e r easily y formed if the temperature is allowed to rise. In the brominating, then, it is necessary t o avoid all rise of teryperature. The Iiel~tylenewas put i n a long tube surrounded by a freezing mixture of sodium sulphate and hydrochloric acid, and air loaded with bromine vapor was sucked through it for six or ten hours. The color of the bromine disappeaxd with each bubble, and the rcaetion was stopped as soonas a perinanent coloration was observed. The thick, oily liquid was then distilled in partial vacuum, boiling quite constantly without the evolution of hydrobromic acid gaP. After the first distillation it was found possible to cornplete the fraotioning under ordinary pressure. The boiling point was 209°-2110 C. (uncorrected.) Only with preat difficulty did Schorlemmer t succeed in
* t
Ber. Chem. Ges. XIII. 1619. AnndenChem. Pharm. lB,m.
IIEPTYLENE FROM HEPTANE O F P. SABINIANA.
23
forming a heptylene broniide or heptylic dibromide from his petroleum-heptane, and it could not be distilled. T h e dibromide prepnred b y Thorpe and Young 1has a spec. grav. 1.5146 (18.5O C ) , and underwent decomposition at the temperature of 150° C-that is, considerably below the boiling point as observed for the dibromide described above. I propose carrying the invcvtigation of this lieptylene and its derivatives still further, as their stability gives promise of interesting results. A careful determination of the specific gravity of the the dibromide will also be made as soon as a larger supply is on hand. $ Aunalen Chem. Pharm. 165,12.
