Structure of 2,6-dimethoxy- and dibenzyloxyquinone-acetone adducts and behaviour of related quinones

Abstract

The properties of dimethoxyquinone-acetone adduct conclusively prove that it involves addition on the the carbonyl group of the quinone at 1-position. It forms two acetates, one, a direct monoacetate and the other, a diacetate derived from a transformation product of the adduct. Since the two methoxyl groups do not sterically deactivate the carbonyl group in position 1, the extent of this effect has been examined by taking 2,6-dibenzyloxyquinone as a suitable example. This is also found to form an adduct involving addition of acetone on the 1-carbonyl group proving thereby that steric factors are not important in this reaction. A number of other quinones have also been studied. They do not form adducts, but undergo various changes such as polymerization or reduction.