AM1 study of C-O fragmentation in the radical anions of benzyl methyl ethers

Abstract

The semiempirical AM1 method is used to study the fragmentation of aryl alkyl ether radical anion with various substituents on the phenyl ring. The aim of this study is to understand the basis for the “spin regioconservation principle” which states that an inherent preference for radical anion scission would occur where the unpaired electron remains on the same side of the scissible bond during the fragmentation process. The benzyl methyl ether radical anion is chosen as a model system in which the two alternative C-O fragmentation processes are compared. We found that in accord with the principle the more favorable one is indeed the one with the odd electron σ* for the product remaining on the same molecule fragment as that of π* for the reactant.