Oxidation of alkoxy-phenols. Part VI. A hemi-acetal from 4-methoxy-2-t-butylphenol

Abstract

Gentle treatment with acid converts the ferricyanide oxidation product, believed to be the dienone (III). of 4-methoxy-2-t-butylphenol into the hemi-acetal (IV). The latter's structure is proved by reduction to the tri-hydroxybiphenyl (V), and by formation of the azodibenzofuran (VII) on reaction with 2,4-dinitrophenylhydrazine. In acid, oxidation of either the hemi-acetal or of the trihydroxybiphenyl (V) gives the dibenzofuran-1,2-quinone (XIII), but in neutral or alkaline solution the dibenzofuran-1,4-quinone (XV). Electron spin resonance spectrometry has been used to examine some of these oxidations.