Electron paramagnetic resonance spectroscopic studies of the electron transfer reaction of Hantzsch ester and a pyrylium salt

Abstract

The oxidation of Hantzsch ester by a pyrylium cation takes place via electron–proton–electron transfer. The reaction was investigated with EPR spectroscopy using TEMPO and DMPO for inhibition and spin trapping, respectively, of the radicals appearing during the reaction. The present in-depth EPR study of the radical reactions of a NADH analogue indicate a complex electron transfer mechanism in the title reaction.