Molecular Tectonics: Control of Reversible Water Release in Porous Charge-Assisted H-Bonded Networks

The combinations of bisamidium dicationic tectons 1-2H⁺ and 2-2H⁺ bearing two OH groups as additional H-bond donor/acceptor sites with [M(CN)₆]³⁻₂ (M = Fe, Co, Cr) anions lead to the formation of robust porous crystals (decomposition temperature in the range of 240−300 °C) offering channels occupied by water molecules. The release and uptake of solvent molecules takes place through a reversible single crystal-to-single crystal transformation. Importantly, the temperature of dehydration can be increased by ca 40 °C through the decoration of the channels by introduction of OH groups on the backbone of the organic tecton.