Studies on the Dibenzo-p-dioxin (Diphenylene Dioxide) Derivatives. XXXVIII. The Color Reaction of Dibenzo-p-dioxin Derivatives in Concentrated Sulfuric Acid with Oxidizing Agents. The Detection by Electron Spin Resonance Spectra.

Abstract

Compounds having a skeleton of dibenzo-p-dioxin (I) show a characteristic color (mostly blue or greenish blue and sometimes violet) in concentrated sulfuric acid with an oxidizing agent such as potassium nitrate. A series of electron spin resonance studies have revealed that the coloring was due to the formation of the cation radicals such as Ia.