The Haber-Weiss mechanism does not apply to the FeII induced fragmentation of primary and secondary hydroperoxides in pyridine. However, it does apply to tertiary hydroperoxides. Steric bulk is an important factor in FeII induced dialkyl peroxide decomposition in pyridine. On the contrary in tetrahydrofuran a different relatively unhindered electron transfer process predominates where the FeII becomes a catalyst.
