Remarkably stable porous assembly of nanorods derived from a simple metal-organic framework

Abstract

A new strategy has been described to create a microporous metal-organic framework by assembling nanorodlike constructs equipped with a complementary hydrogen-bonding surface. Guest-accessible channels are located in the internanorod space generated by the self-assembly of the nanorodlike constructs via complementary hydrogen bonding. Thus, reaction of a hydrogen-bond-equipped and conformationally flexible ligand such as N,N'-bis(3-pyridyl)urea with CuSO₄ resulted in the formation of a stable, guest-free microporous MOF wherein a nanorodlike construct is formed that is further self-assembled into a microporous metal-organic framework via self-complementary hydrogen bonding involving a urea backbone and sulfate anion. Because of conformational flexibility, a one-dimensional zigzag coordination polymeric network is also formed. The structures are characterized mainly by single-crystal X-ray diffraction techniques.