Reversible single-crystal-to-single-crystal guest exchange in a 3-D coordination network based on a zinc porphyrin

A self-complementary tecton based on a zinc porphyrin core bearing two pyridines at the opposite meso positions leads to the formation of a 3-D coordination network in the crystalline phase which offers channels which are filled with solvent molecules; reversible exchange of the guest molecules has been proven to take place in a single-crystal-to-single-crystal type transformation demonstrating the robustness of the coordination framework.