Encapsulation of photoswitchable molecules in a self-assembled supramolecular cage

In the present research, we investigated properties of the complex of new heterocyclic photoswitchable pyrazole in the confined environment of the flexible organometallic cage. We prepared and characterized the water-soluble complex and observed the unusual crystal structure dynamics of it. Afterward, we managed to reversibly switch it in the solution observing the change of guest/host relation with increasing of the guest bulkiness. Using the comprehensive NMR research we confirmed the binding of an unstable guest under the fast exchange conditions. We noticed unusual supramolecular catalysis of Z-E isomerization, studied the mechanism of it with the series of kinetic experiments. Our observation proved the emergence of a curious chemical system from simple azoheteroarene photoswitch and organometallic supramolecular cage. We believe that constructing chemical systems combining photoswitchable molecules and supramolecular hosts, soluble may be perspective for developing new drug-delivery facilities controlled by light or “greener” solar sources of energy.