Synthesis of bowl-shaped polycyclic aromatic hydrocarbons via palladium-catalyzed intramolecular arylation reactions

摘要

Treatment of the benzannulated enediyne 11 with potassium tert-butoxide in refluxing toluene for 12 h produced 15 via a cascade sequence of cyclization reactions. Two subsequent palladium-catalyzed intramolecular arylation reactions then afforded the bowl-shaped polycyclic aromatic hydrocarbon 16. The X-ray structures of 16 and two closely related molecules show the presence of significant curvatures.