Porous Macroligands: Materials for Heterogeneous Molecular Catalysis

Abstract

The integration of catalytically active centers into a solid support without any loss of performance compared to the homogeneous analogue remains a major challenge. In this context, solid macroligands can be regarded as the key element to combine the advantages of homogeneous and heterogeneous catalysis. Porous materials such as periodic mesoporous organosilica, metal‐organic frameworks, porous organic polymers or covalent‐organic frameworks fulfill all requirements of a macroligand acting as a solid ligand of a molecular complex. They all can be tuned at the molecular scale to adapt the properties of the catalyst for a given application. This important feature also allows to directly compare different macroligands, regardless of their nature, and to choose the most appropriate for a target application.

Molecular Porous Photosystems Tailored for Long‐Term Photocatalytic CO2 Reduction

“…Our synthetic strategy consists in integrating an active organometallic catalyst into a photosensitive porous organic matrix. We have chosen monomers based on photoactive perylene or pyrene cores to synthesize microporous macroligands that consist of alternating photosensitizers and metal binding sites called hereafter perylene‐ alt ‐bipyridine‐conjugated microporous polymers (PerBpyCMP) and pyrene‐ alt ‐bipyridine‐CMP (PyBpyCMP). Then the Cp*Rh catalytic synthon was coordinated to the different frameworks to obtain the heterogeneous photocatalysts Cp*Rh@PyBpyCMP and Cp*Rh@PerBpyCMP (Figure a), following a well‐established grafting procedure …”

Heterogenization of a Molecular Ni Catalyst within a Porous Macroligand for the Direct C–H Arylation of Heteroarenes

“…To change the paradigm of molecular catalytic processes for fine chemical synthesis, we introduced recently the concept of solid porous macroligand for heterogenized molecular catalysis (Scheme ). Having molecularly defined active sites, porous macroligands have been found to drive the activity and the selectivity of heterogenized catalytic processes on a similar way as molecular ligands but with the advantage of the structuration in a three-dimensional framework , and the confinement within a porous nanospace. , …”

Synthetic and computational assessment of a chiral metal–organic framework catalyst for predictive asymmetric transformation

“…26 Despite numerous examples of homochiral amidofunctionalized MOF including prolinamide moieties, 27 there is no report so far of amido-functionalized MOF used either as a porous macroligand, i.e. a solid acting as the organic ligand in the corresponding molecular complex, [28][29][30] for such organometallic complexes or for asymmetric transfer hydrogenation catalysis.…”