The cleavage of the radical cations of benzyl phenyl ether and 4,4’-dimethoxybibenzyl at low temperature (82 degrees C) has been studied. The cation radicals are formed by one-electron oxidation using Fe-III(1,10-phenanthroline)(3)(ClO4)(3). Cleavage of benzyl phenyl ether has been achieved using a catalytic amount of Fe(III) and air to reoxidize Fe(II) to Fe(III). While the dominant chemical process is cleavage of the bond beta to the aromatic rings, substantial amounts of less reactive rearranged and higher molecular weight materials are formed. These competing reactions are expected to become more important in diffusionally limited coals. We conclude that radical cation mechanisms are not good candidates for low-temperature coal conversion processes because of the propensity of the systems to undergo aromatic substitution reactions and rearrangements to less reactive structures, processes which do not lead to depolymerization.