Substituent Effects on the Decomposition of Bis(tert-butylperoxy)cycloalkanes

Article abstract of DOI:10.1021/jo00059a029

Decompositions of bis(tert-butylperoxy)cycloalkanes have been carried out in cumene and n-alkanes at temperatures of 80-120 deg C and have been compared mainly with the decomposition of tert-alkyl tert-butyl peroxides in order to investigate substituent effects on the homolytic scission of one O-O bond in gem-diperoxides.The decomposition rates of bis(tert-butylperoxy)cycloalkanes are much faster than those of tert-alkyl tert-butyl peroxides; the decomposition rates of the cycloalkanes decrease in the following order: cyclopentane > 3,5,5-trimethylcyclohexane > cyclohexane > cyclooctane > cyclododecane.The effect of ring size on the decomposition and the isokinetic relationships between the activation parameters suggest that stabilization of the transition state by electron donation from the cycloalkyl substituents and repulsion between lone-pair electrons on different peroxy oxygen atoms in the ground state are important factors in the decomposition of gem-diperoxides.