We reported that a benzyl-type binaphthyl disulfone could be conveniently converted into dibenzophenanthrene. Thus, racemic 1 was treated with lithium diisopropylamide (LDA) afforded dl-dibenzophenanthrene in a moderate yield, together with an unknown benzensulfonyl-substituted derivative 2. The structures were confirmed by MS, 1H, 13C NMR and elemental analysis. The reaction might involve the initial intramolecular nucleophilic substitution to produce an intermediate 3, followed by elimination of benzenesulfinic acid to form dibenzophenanthrene.
