aes 
. 
os ; 
i Hedtocarbons: Sas 
/ 
 Isepentane and 2 isoprene. ae publication by O. Aschan 4) on a erivatives of the petroleum 
yentanes and some of their homologues, deals, amongst others, also with isoprene and 
Boyt alcohol. The author investigated the action of chlorine on paraffins, more especially 
the pentanes boiling from 30 to 38°, moreover a hexane, and the first runnings of the 
pentanes, “b.p. 10 to 120, Aschan succeeded, when starting from isopentane, to syn- 
th esise the principal constituents of fusel oil, 2.e., both primary isoamyl alcohols (iso- 
butyl carbinol and sec. butyl carbinol). The method devised permits of preparing these 
bodies cheaply and in unlimited _quantities, as isopentane occurs in all hitherto known 
_ petroleum: varieties in considerable amount. aye Ae 
_ Furthermore, he endeavoured to make use of the asopentane or of atten suitable 
petroleum hydrocarbons (such as n- -butane, n-pentane, various hexanes, more especially 
_n-diisopropyl). for the preparation of isoprene and its homologues. He proved that all 
_ isopentyl chlorides, by suitable elimination of hydrogen chloride, pass over into tri- 
-methylethylene, some of the chlorides thus suffering a rearrangement. Under certain 
: conditions, trimethylethylene unites with chlorine, forming the corresponding dichloride, 
irom which bases abstract hydrogen chloride with formation of isoprene. Equally, the 
Biichlotdisopentanes obtained by direct chlorination of. isopentane (amongst which -tri- 
. _ methylethylene chloride seems to be present) pele antag when sufficient heat is 
| applied in eliminating the hydrogen’ chloride. - | 
4g On studying the literature, Aschan found that the former ivectinatord never had 
in hand the derivatives of isopentane, but those of n-pentane. 
, In addition, Aschan communicates his observations on the distillation of caoutchouc 
and on derivatives of an isoprene obtained by heating vapours of turpentine oil. 
_ When distilling rubber he obtained, in addition to only 1,9 per cent. crude isoprene, 
13 percent. of a hydrocarbon (terpene?) hitherto not further investigated; b. p.170 to 175°. 
4 On pyrogenetic decomposition of the vapours of turpentine oil, about 5 percent. of ~ 
3 crude isoprene, b. p. 30 to 402, resulted ; in the last runnings, b. p. not exceeding 100°, : 
Pat least two more hydrocarbons were present, amongst them particularly abundant a 
hydrocarbon unstable towards potassium permanganate, hence unsaturated ; b. p. about 
70°. The higher-boiling fractions contained, besides undecomposed TECD Stes benzene. 
- and the next homologues thereof. © | 
4 _ Finally, Aschan reports on new high- molecular hydrocarbons derived from isoprene. | 
_ Under suitable conditions isoprene combines with unsaturated hydrocarbons, such as 
" amylene, pinene, camphene, as well as with itself, forming very high-molecular compounds. 
_ They are amorphous, but lack entirely the physical properties of caoutchouc. isoprene ; 
_ condenses likewise with ORIEN dipentene, and SIV ESTEET: 
_ In connection with the investigation mentioned before we report on a paper published 
"likewise by O. Aschan?), on the pyrogenic decomposition of the residues of Russian petroleum 
_ (masut); new suggestions for the economic utilisation of petroleum. In this. publication, the 
author is of opinion that the residue obtained in refining petroleum, commonly termed 
“masut’, is a suitable raw material for the preparation of isoprene. He succeeded in 
"obtaining isoprene amongst the distillation products of masut, and in converting it into 
_ caoutchouc, as ne as in determining the amount of isoprene and the other hydro- 
i ty Ofversigt of F inska Teedsbuten Speetetohe Forhandlingar 68 (1915); Chem. Zentralbl. 1918, II. 939, 955. 
$ om . 4) Ofversigt af Finska Vetenskups-Societetens Foirhandlingar. Helsingsfors 1919. 
