368 Hillyer—Action of Aluminum Chloride , etc. 
Gustavson, a Russian chemist, has shown that aluminum 
bromide reacts on many substances of the fatty series, including 
petroleum ether, when a stream of hydrobromic acid is passed 
in or when ethyl bromide is present. But so far as can be as¬ 
certained from the only source available, viz., the Russian 
correspondence of the Bulletin de la Societe Chimique of Paris, 
he does not note any reaction taking place between aluminum 
bromide and petroleum ether when they alone are present, nor 
does he mention any reaction of aluminum chloride on petroleum 
ether or paraffin hydrocarbons. 
When aluminum chloride is brought into petroleum ether and 
the temperature is raised to 40° or 50°, there is evolution of 
hydrochloric acid and of combustible gases. This reaction 
takes place even at ordinary temperatures, but more slowly. 
The contents of the flask after the reaction is over is in two 
layers, the unchanged petroleum ether and a brown horn-like sub¬ 
stance insoluble in petroleum ether, but soluble in chloroform. 
It probably corresponds to the substance C 4 H 8 AlBr 3 which 
Gustavson found as a product of many reactions in which AlBr 3 
acts on fatty compounds. On account of its hygroscopic char¬ 
acter it would be very hard ta bring it into form to analyze, 
and no attempts have been made in this direction. When the 
substance is treated w T ith water much heat is evolved and a 
brownish liquid results which floats on water. Repeated frac¬ 
tional distillations even under diminished pressure fail to sep¬ 
arate any product of even approximately constant boiling point. 
The range of temperature shown by the fractions is from the 
boiling point of the petroleum ether up to 350° and beyond. 
At 200° there is evidence of decomposition. The higher frac¬ 
tions which are brown or yellowish tars have a pleasant peculiar 
odor. 
Petroleum ether is a mixture of hydrocarbons principally of 
the paraffin or saturated series. It is the common idea that the 
parraffin hydrocarbons are extremely stable and not acted on 
except by the halogens. The reaction described is of interest, 
since it is the action of a simple salt on these supposed stable 
compounds. In order to study it more carefully some of the so- 
called turpentine of the California digger pine was obtained and 
