Transalkylation of polycyclic aromatics catalyzed by trifluoromethanesulfonic acid

Normal alkyl (C/sub 4/-C/sub 10/) and cycloalkyl (C/sub 6/, C/sub 5/) groups are transferred between aromatic rings of different degree of condensation (one to four rings) in the presence of trifluoromethanesulfonic acid. The structure of the compounds studied is relevant to chemical structures in fossil fuels. The rate of transalkylation exhibits an unexpected dependence upon the concentration of acid: for each system, a minimum concentration of acid is necessary to initiate the reaction; as the concentration is increased beyond this threshold, the reaction rate increases dramatically. 24 references, 3 figures, 4 tables.