Palladium-Catalyzed Cyclization: Regioselectivity and Structure of Arene-Fused C Derivatives.

The palladium-catalyzed cyclization on the fullerene C cage has been achieved using several aryl halides and C. This reaction was found to be accelerated by the addition of pivalic acid, which can be rationally explained by the computational study based on the concerted metalation-deprotonation mechanism. We also demonstrated the regioselective π-functionalization using prefunctionalized designed molecules possessing the same substructure on the C cage. The single crystal X-ray analysis and electrostatic potential map revealed that the orientation of entrapped HO inside the naphthalene-fused open-cage C derivative is electrostatically demanded due to the naphthalene-fusion and construction of the opening.