Reactions that lead to fuel instability can be closely linked to the presence of active oxygen species such as hydroperoxides. An increasing body of evidence links oxidation reactions and the increasing polarity caused by incorporation of heteroatoms into the sediment precursors that form insoluble macromolecular compounds. The active oxygen compounds present in fuels are alkyl and aromatic hydroperoxides. Cumene hydroperoxide represents a logical choice for an active oxygen compound that could be present in a middle distillate fuel. This paper reports on the reactions of cumene hydroperoxide in benzene solvent for a reaction temperature range of 130-170-degrees-C for a 30-min time period. The complete slate of products is presented along with a suggested mechanism to explain the observed products and the implications for fuel instability reactions.