A 1,5-Bifunctional Organomagnesium Reagent for the Synthesis of Disubstituted Anthracenes and Anthrones

The preparation of a 1,5-bifunctional organomagnesium alkoxide reagent by a deprotonation–magnesiation sequence is described. This reagent reacts with carboxylic acid esters to incorporate the carboxyl carbon atom of the ester into the newly formed ring. The magnesium bisalkoxide resulting from this double nucleophilic attack is subsequently transformed in situ into halogenated disubstituted anthracenes, monosubstituted anthracenes, anthrones, or 9-substituted dihydroanthracene-cis-diols by variation of the acidic workup procedures.