Interaction of duroquinone lowest triplet with amines

Abstract

The reaction of the lowest triplet of duroquinone, ³Q, with tertiary amines (triethylamine TEA, diethylaniline DEA, triphenylamine TPA) has been investigated by laser flash absorption spectroscopy in non-polar (cyclohexane or benzene) and polar (acetonitrile) solvents. Three pathways of ³Q deactivation involving an exciplex as intermediate were observed: (i) an electron transfer to ³Q from TPA and DEA in a polar solvent, (ii) a H atom transfer to ³Q from DEA in a non-polar solvent and from TEA in a non-polar or a polar solvent, (iii) a physical quenching of ³Q by TPA in a non-polar solvent with no photoreduction products.