ON THE ACTION OF ALUMINUM CHLORIDE ON SATU 
RATED HYDROCARBONS. 
HOMER W. HILLYER, PH. D., 
Assistant Professor of Organic Chemistry , University of Wisconsin. 
The reaction discovered by Friedel and Crafts and called by 
their name, is one of the most widely applicable methods of 
synthesis used. By it can be built up from simple hydrocar¬ 
bons of the benzene series derivatives belonging to almost all of 
the classes known. As an example a simple case may be given: 
When acetyl chloride and benzene are brought together no reac¬ 
tion takes place, but if to the mixture a little anhydrous 
aluminum chloride is added, there is a rapid evolution of hydro¬ 
chloric acid and a tarry mass is left which by the action of the 
water is changed to aluminum chloride and a ketone, aceto- 
phenon. Leaving out the intermediate steps, the reaction may 
be interpreted by saying that under the influence of the alum¬ 
inum chloride one hydrogen atom of the benzene and the chlo¬ 
rine of the acetyl chloride have formed hydrochloric acid and 
the residues before joined to the hydrogen and chlorine have 
joined to form our new ketone. In the same way any organic 
compound containing chlorine can be made to give up its chlo¬ 
rine in favor of an aromatic hydrocarbon residue. 
In using the Friedel and Crafts reaction for the synthesis of 
aromatic compounds it is sometimes desirable to use a solvent 
either to bring solid substances into solution or to dilute 
liquid substances in order to prevent too great intensity 
of action. Carbon bisulphide and petroleum ether are the solv¬ 
ents used by chemists and recommended in the text books and 
laboratory guides. It is to raise objection to the use of the lat¬ 
ter solvent that this note is presented. If ohe reaction takes 
place readily and at a low temperature petroleum ether may in 
some cases be used with propriety, but it should not be used in 
all cases. 
