The development of strong covalent interactions in inner sphere electron transfer reactions between cation radicals and neutral molecules

Abstract

The cation radical Diels–Alder reactions of a series of meta and para substituted aryl cis-prop-1-enyl ethers with 2,3-dimethylbuta-1,3-diene catalyzed by tris(4-bromophenyl)aminium hexachloroantimonate have been studied mechanistically. The reactions are found to occur primarily via an indirect route involving cation radical cyclobutanation followed by cation radical vinylcyclobutane rearrangement. Kinetic studies reveal that the ionization of these ethers to the corresponding cation radicals occurs by an inner sphere mechanism.