Cycloparaphenylene-Type Hoops with Adaptive Cavities Derived from N,N′-diphenyldihydrodibenzo[a,c]phenazine

Cycloparaphenylenes (CPPs) possess radial π-conjugation structures and host-guest capability. Herein, we report the synthesis of novel CPP analogues featuring a flexible N,N'-diphenyldihydrodibenzo[a, c]phenazine (DPAC) unit. These molecules feature adaptive cavities that enable efficient host-guest interactions with species such as [2,2]PCP. Crystallographic analysis revealed structural reorganization of the macrocycle upon guest incorporation, supported by DFT calculations, confirming geometric adaptation during guest complexation. These findings demonstrate guest-induced conformational adaptability in the DPAC-[n]CPP system.