The functionalization of an imine-based layered covalent organic framework (COF), containing phenanthroline units as ligands, has allowed the obtention of a heterobimetallated material. Photoactive Ir and Ni fragments were immobilized within the porous structure of the COF, enabling heterogeneous light-mediated Csp 3 –Csp 2 cross-couplings. As radical precursors, potassium benzyl- and alkoxy-trifluoroborates, organic silicates, and proline derivatives were employed, which brings out the good versatility of Ir,Ni@Phen-COF . Moreover, in all the studied cases, an enhanced activity and stability have been observed in comparison with analogous homogenous systems.

Photochemistry of extended polyimine COF structures with laminar, spherical and 3D architectures has been examined. We show that these materials, composed by undecorated phenyl rings and imine fragments, can act as photocatalyts in oxidative transformations, being the crystalline laminar material the most active photocatalyst. The sulfoxidation reaction proceeds with good yields for a large variety of different sulfides. This process was carried out under visible light conditions (20 W), ethanol/ H 2 O as solvent, and the heterogeneous porous material can be recycled up to 9 times. The crystallinity favours the behavior as photocatalyst of laminar and spherical COFs whereas any particular effect on the 3D material activity was observed. Sulfoxidation reaction mainly proceeds through an energy transfer mechanism using crystalline laminar material. In addition, these materials as photocatalysts were used for the oxidation of phenyl boronic acid into phenol. . a) Catalytic runs in the oxidation of sulfide 2 a to 3 a in nine consecutive 24 hours catalytic runs by addition of 0.3 mmol of sulfide 2 a after each cycle (see S.I. for further information). The output of the catalytic reaction is expressed as mmol of 3 a generated per cycle. Characterization after one catalytic cycle: b) SEM image of crystalline Laminar-COF 1 b c) FT-IR (black colour before catalysis and red colour after catalysis) d) PXRD (black colour before catalysis, red colour, after catalysis). Scheme 1. Mechanistic plausible scenarios for photocatalytic aerobic sulfoxidation reactions (PC = photocatalyst).

The review summarizes the state-of-the-art of C–H active transformations over crystalline and amorphous porous materials as new emerging heterogeneous (photo)catalysts.

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Among the different alternatives for catalysis using metal–organic frameworks (MOFs) or covalent organic frameworks (COFs), photocatalysis has remarkably evolved during the last decade. Photocatalytic reticular materials allowed recyclability and easy separation of catalyst from the product, also reaching the activity and selectivity commonly observed for molecular systems. Recently, photocatalytic MOFs and COFs have been applied to synthetic applications in order to obtain organic molecules of different complexity. However, although a good number of works have been devoted to this issue, an updated comprehensive revision on this field is still needed. The aim of this review was to fill this gap covering the following three general aspects: (1) common strategies on the design of reticular photocatalytic materials, (2) a comprehensive discussion of the photocatalytic organic reactions achieved by the use of COFs and MOFs, and (3) some critical considerations highlighting directions that should be considered in order to make advances in the study of photocatalytic COFs and MOFs.