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

The combinations of bisamidium dicationic tectons <b>1</b>-2H<sup>+</sup> and <b>2</b>-2H<sup>+</sup> bearing two OH groups as additional H-bond donor/acceptor sites with [M(CN)<sub>6</sub>]<sup>3−</sup><sub>2</sub> (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 <i>ca</i> 40 °C through the decoration of the channels by introduction of OH groups on the backbone of the organic tecton.