Batch versus Flow Acetalization of Benzaldehyde with HKUST-1: Diffusion Pathways and Performance Comparison

α,β-Enone Borylation by Bis(Pinacolato)Diboron Catalyzed by Cu3(BTC)2 Using Cesium Carbonate as a Base

Cu₃(BTC)₂ (BTC: 1,3,5-benzenetricarboxylate) as a heterogeneous catalyst in the presence of cesium carbonate as a base is reported for the borylation of α,β-conjugated enones by bis(pinacolato)diboron (B₂pin₂). According to the hot-filtration test, Cu₃(BTC)₂ is acting as a heterogeneous catalyst. Further, Cu₃(BTC)₂ exhibits a wide substrate scope and can be reused in consecutive runs, maintaining a crystal structure as evidenced by powder X-ray diffraction (XRD). A suitable mechanism is also proposed for this transformation using Cu₃(BTC)₂ as catalyst.

Metal organic frameworks as solid catalysts for liquid-phase continuous flow reactions

This Feature Article describes the recent developments in the use of MOFs as catalysts under continuous flow conditions illustrating that these materials can meet the required stability.

Emerging porous materials in confined spaces: from chromatographic applications to flow chemistry

Porous materials confined within capillary columns/microfluidic devices are discussed, and progress in chromatographic and membrane separations and catalysis is reviewed.

Graphene inclusion controlling conductivity and gas sorption of metal-organic framework

A general approach to prepare composite films of metal-organic frameworks and graphene has been developed. Films of copper(ii)-based HKUST-1 and HKUST-1/graphene composites were grown solvothermally on glassy carbon electrodes. The films were chemically tethered to the substrate by diazonium electrografting resulting in a large electrode coverage and good stability in solution for electrochemical studies. HKUST-1 has poor electrical conductivity, but we demonstrate that the addition of graphene to HKUST-1 partially restores the electrochemical activity of the electrodes. The enhanced activity, however, does not result in copper(ii) to copper(i) reduction in HKUST-1 at negative potentials. The materials were characterised in-depth: microscopy and grazing incidence X-ray diffraction demonstrate uniform films of crystalline HKUST-1, and Raman spectroscopy reveals that graphene is homogeneously distributed in the films. Gas sorption studies show that both HKUST-1 and HKUST-1/graphene have a large CO2/N2 selectivity, but the composite has a lower surface area and CO2 adsorption capacity in comparison with HKUST-1, while CO2 binds stronger to the composite at low pressures. Electron paramagnetic resonance spectroscopy reveals that both monomeric and dimeric copper units are present in the materials, and that the two materials behave differently upon hydration, i.e. HKUST-1/graphene reacts slower by interaction with water. The changed gas/vapour sorption properties and the improved electrochemical activity are two independent consequences of combining graphene with HKUST-1.