Quest for Zeolite-like Supramolecular Assemblies: Self-Assembly of Metal–Organic Squares via Directed Hydrogen Bonding

Abstract

Our conceived approach based on the directed assembly of functional metal–organic squares (MOSs), 4-membered ring (4MR) building units, permitted the construction of two novel zeolite-like supramolecular assemblies (ZSAs), namely [Co4(ImDC)4(En)4]⋅9 H2O⋅1.5 DMF (ZSA-10) and [Co4(ImDC)4(En)4]⋅7 H2O (ZSA-11) (H3ImDC=4,5-imidazoledicarboxylic acid, En=ethylenediamine, DMF=N,N-dimethylformamide). The elected MOSs encompass both trans- and cis-coordinated nodes, offering complementary peripheral functional groups for their directed assembly into zeolite-like topologies via supramolecular hydrogen bonding interactions. Distinctly, ZSA-10 possesses the underling MER zeolite topology and is the only pure MER framework material (without any supporting templates) exhibiting permanent porosity up to now. ZSA-11 has the underlying ABW topology together with one type of narrow channel.