Highly brominated anthracenes as precursors for the convenient synthesis of 2,9,10-trisubstituted anthracene derivatives

When 9,10-dibromoanthracene was treated with bromine in CCl4 without a catalyst, 1,2,3,4,9,10-hexabromo-1,2,3,4-tetrahydroanthracene (3) was obtained in 95% yield in the absence of other stereoisomers or rearomatization products. We investigated the base-induced elimination reaction of hexabromide 3 under various conditions. Pyridine-induced elimination of hexabromide 3 afforded 2,9,10-tribromoanthracene (12) in 75% yield, and tribromide 12 was transformed to trimethoxy compound 13 and trinitrile 14 by copper-assisted nucleophilic substitution reactions.