Cooperativity in Molecular Recognition of Porphyrin Clefts

The electron-rich cleft cavities of porphyrin-based molecular tweezers encapsulate various electron-deficient guest molecules via π-π stacking and donor-acceptor interactions. In this presentation, we will describe negative cooperativity in the molecular recognition of a trisporphyrin host molecule possessing two cleft cavities. A 1:2 host-guest complexation of the trisporphyrin host with various electron-deficient guest molecules showed strong negative cooperativity. The quantitative discussion of the negative cooperativity was provided by a detailed analysis using isothermal titration calorimetry. 1) Hisano, N.; Kodama, T.; Haino, T., Chem. Eur. J. 2023, 29, e202300107 2) Hisano, N.; Haino, T., J. Org. Chem. 2022, 87, 4001-4009. Figure 1