Regioselective electrophilic addition vs epoxidation of mCPBA towards anti-Bredt olefin of fulleroid

The mCPBA oxidation of methano-bridged [5,6] open fulleroid 1 anomalously resulted in the selective electrophilic addition at the bridgehead anti-Bredt double bond rather than the usual epoxidation. The mechanistic preference for the unprecedented stepwise addition of mCPBA vs the concerted epoxidation was explained in terms of the notable π-orbital misalignment (>30°) based on the B3LYP/6-31G(d) level calculation.