The hydroxyperoxides R2CH (OOR1) OH (R1= CH3, C2H5; R2= CH3, i-C3H7) and their isomeric alkoxyhydroperoxides R2CH (OOH) OR1 can be differentiated by their polarographic behavior. These hydroxyperoxides are not produced in the ozonolysis of trans 4-methyl-2-pentene in the presence of methanol or ethanol. It is concluded that the zwitterionic structure does not participate in the mechanism of ozonide formation.