Redox-Active Dihydrophenazine-Based Macrocycle: Synthesis, Conformation-Adaptive Behavior and Host-Guest Complexation with Tetracyanoquinodimethane

A novel macrocycle based on conformation-adaptive and electron-rich dihydrophenazine was designed and synthesized. On the one hand, the macrocycle showed host-guest interactions with tetracyanoquinodimethane (TCNQ) driving by charge transfer interaction between them. Meanwhile, host-guest complexation was accompanied by fluorescence quenching and conformational change of the macrocycle. On the other hand, the oxidation of the macrocycle resulted in its diradical cation analogue and induced the release of the guest molecule TCNQ, thereby accomplishing reversible binding dynamics. Therefore, this work well illustrates the chemical and structural versatility of dihydrophenazine in the synthesis of macrocycles and their host-guest chemistry.