Supramolecular interactions impacting on the water stability of tubular metal-organic frameworks

Tubular MOFs based on copper(II) phosphinates and bipyridine have been found to be highly stable in water. However, the possibility to form more dense and stable phases could affect their water stability, leading to slow and spontaneous transformations driven by the hydrolysis of the metal-ligands bonds. As a matter of fact, two structurally related MOFs have a very different water stability that, for one of the two MOFs, can be attributed to the existence of more stable phases that induces a slow transformation in water. For the other MOF, the non-existence of a related more stable phase, probably due to an unfavorable predicted crystal packing, yields an outstanding stability in hot water.