Hydrogénation de sels de flavylium: formation de composés heptacycliques; structure radiocristallographique du [tétrahydro‐10b,10c,16,16a‐diméthyl‐16,16a‐méthylène‐10b,16‐5a H ‐di(benzo[1]pyranno)[4,3‐ b :3′,4′,‐ c ;2,3:2′,3′]‐benz[1]oxépinyl‐5a]‐2‐phénol

Hydrogenation of Flavylium Salts: Formation of Heptacyclic compounds; X‐Ray Crystal Structure of 2‐[10b,10c,16,16a‐Tetrahydro‐16,16a‐dimethyl‐10b,16‐methylene‐5a H ‐di[1]benzopyrano[4,3‐ b :3′,4′ ‐ c ; 2,3:2′,3′][1]benzoxepin‐5a‐yl]phenol The hydrogenation of flavylium salts 1 either by catalytic reduction or by chemical reduction afforded the unexpected heptacyclic compound 2 , the structure of which was determined by X‐ray analysis. The latter was confirmed by 1 H‐NMR and mass spectra.