Two Isostructural URJC-4 Materials: From Hydrogen Physisorption to Heterogeneous Reductive Amination through Hydrogen Molecule Activation at Low Pressure

Herein, two novel isostructural metal-organic frameworks (MOFs) M-URJC-4 (M = Co, Ni; URJC = "Universidad Rey Juan Carlos") with open metal sites, permanent microposity, and large surface areas and pore volumes have been developed. These novel MOFs, with polyhedral morphology, crystallize in the monoclinic P2₁/c space group, exhibiting a three-dimensional structure with microporous channels along the c axis. Initially, they were fully characterized and tested in hydrogen (H₂) adsorption at different conditions of temperature and pressure. The physisorption capacities of both materials surpassed the gravimetric H₂ uptake shown by most MOF materials under the same conditions. On the basis of the outstanding adsorption properties, the Ni-URJC-4 material was used as a catalyst in a one-pot reductive amination reaction using various carbonyl compounds and primary amines. A possible chemical pathway to obtain secondary amines was proposed via imine formation, and remarkable performances were accomplished. This work evidences the dual ability of M-URJC-4 materials to be used as a H₂ adsorbent and a catalyst in reductive amination reactions, activating molecular H₂ at low pressures for the reduction of C═N double bonds and providing reference structural features for the design of new versatile heterogeneous materials for industrial application.

Novel alkaline earth metal–organic frameworks with thiophene groups for selective detection of Fe3+

This work demonstrates that the alkaline earth ion radii play an important role in coordination numbers and topologies for constructing MOFs, and these MOFs can be used as fast-response fluorescence sensors for the detection of Fe³⁺.

The effect of functional groups in the aqueous-phase selective sensing of Fe(iii) ions by thienothiophene-based zirconium metal–organic frameworks and the design of molecular logic gates

The effect of functional groups in the fluorescence sensing of Fe(iii) ions in aqueous medium by four thienothiophene-based Zr MOFs is discussed.

Dimensionality of luminescent coordination polymers of magnesium ions and 1,1′-ethynebenzene-3,3′,5,5′-tetracarboxylic acid modulated by structural inducing agents

Crystal structure diversity and dimensionality of three Mg²⁺-based CPs, which emit bright ligand-based luminescence at ambient conditions, are modulated by reaction temperature and structural induction agents.

Cadmium–1,4-cyclohexanedicarboxylato coordination polymers bearing different di-alkyl-2,2′-bipyridines: syntheses, crystal structures and photoluminescence studies

Cd(ii) polymers, in acetone, can be used as luminescent materials for detection of CH₃CN.

Intense greenish phosphorescence emission under ambient conditions in a two-dimensional lead(ii) coordination polymer with a 1,1′-ethynebenzene-3,3′,5,5′-tetracarboxylate ligand

A new 2D Pb²⁺-based coordination polymer emits intense greenish phosphorescence in the solid state under ambient conditions with a quantum yield of 1.5% and a phosphorescence lifetime of 4.17 ms.

Solvothermal self-assembly of Cd2+ coordination polymers with supramolecular networks involving N-donor ligands and aromatic dicarboxylates: synthesis, crystal structure and photoluminescence studies

Structural, solid state luminescence of Cd(ii) coordination polymers and detection of acetone by CP1via luminescence quenching have been discussed.