The Reactions of an o-Quinone Monoimide with Some Phenols

Article abstract of DOI:10.1021/jo00300a018

The o-quinone monoimide N-(2,4-dichloro-6-oxo-2,4-cyclohexadien-1-ylidene)-4-nitrobenzamide (1) reacts with 2,6-dimethoxy-, 2,6-dimethyl-, and 2,6-dichlorophenols (2a-c) to form N-(2,4-dichloro-6-hydroxyphenyl)-N-(3,5-dimethoxy-, 3,5-dimethyl-, 3,5-dichloro-4-hydroxy)-4-nitrobenzamides (3a-c), respectively.Oxidation of 3a by 1 and 3b by DDQ lead to N-aryl-p-iminoquinones 4a,b.Oxidative dimerizations by either C-C or C-O coupling occur when 1 is admixed with the sterically hindered 2,6-di-tert-butyl-, 2,4-di-tert-butyl-, 4-bromo-2,6-di-tert-butyl-, and 2,4,6-tri-tert-butylphenols.