Abstract
In continuation of the previous work on the syntheses of pyrrogallol-methylene-bis derivatives to obtain effective antioxidant for vitamin A, systematic syntheses were carried out on hydroquinone derivatives, ω, ω'-bis(2, 5-dihydroxyphenyl)alkanes and ω, ω'-bis(2-hydroxy-5-methoxyphenyl)alkanes. The former was obtained generally by the condensation of hydroquinone dimethyl ether and dicarboxylic chloride by the Friedel-Crafts reaction to the ketones, which were catalytically reduced, and finally demethylated to the objective compounds. The latter was obtained by acetylation of the hydroxyketones, formed during the Friedel-Crafts reaction, and catalytic reduction of its product to the objective compounds. Antioxidant action of these derivatives was tested by the decomposition rate of vitamin A acetate, as reported before, and all the hydroquinone derivatives showed antioxidant activity, and ω, ω'-bis(2-hydroxy-5-methoxyphenyl)alkanes, in which one of the hydroxyls had been methylated, showed especially good antioxidant activity.
