An Oxidopyrylium Cyclization/Ring‐Opening Route to Polysubstituted α‐Hydroxytropolones.

Title compounds are generated by a BCl3-mediated ring-opening/aromatization/demethylation process of oxabicyclo[3.2.1]octenes which are obtained from the cycloaddition of oxidopyrylium triflates (I) with various alkynes.