Preparation and Property of 2-(3′,5′-Di-Tert-Butylphenyl-4′-Oxyl)-4,4,5,5-Tetramethyl-4,5,-Dihydro-1h-Imidazole-3-Oxide-1-Oxyl

Abstract

Title compound, a cross-conjugated biradical with phenoxylnitronyl nitroxide structure, was prepared by the lead dioxide oxidation of a p-hydroxyphenyl nitronyl nitroxide, 2-(3,5-di-tert-butyl-4-hydroxyphenyl)-4,4,5,5-tetramethyl-4,5,-dihydro-1H-imidazole-3-oxide-1-oxyl (1b), and was characterized by ESR spectroscopy. On the other hand, the y-radiolysis in a freon matrix and the anodic or chemical oxidation of 1b did not generate 2b but lead to the formation of a phenol-substituted nitronyl nitroxide cation 3b. Thus, a stable acid/base pair with different spin multiplicities, 2b and 3b, could be prepared independently.