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This study investigates the site‐directed immobilization of a hybrid catalyst bearing a biquinoline‐based‐Pd(II) complex (1) and a robust laccase within cavities of a silica foam to favor veratryl alcohol oxidation. We performed the grafting of 1 at a unique surface located lysine of two laccase variants, either at closed (1⊂UNIK157) or opposite position (1⊂UNIK71) of the enzyme oxidation site. After immobilization into the cavities of silica monoliths bearing hierarchical porosity, we show that catalytic activity is dependent on the orientation and loading of each hybrid, 1⊂UNIK157 being twice as active than 1⊂UNIK71 (203 TON vs 100 TON) when operating under continuous flow. These systems can be reused 5 times, with an operational activity remaining as high as 40 %. We show that the synergy between 1 and laccase can be tuned within the foam. This work is a proof of concept for controlling the organization of a heterogeneous hybrid catalyst using a Pd/laccase/silica foam. [ABSTRACT FROM AUTHOR]

We describe the synthesis and characterization of a new mononuclear palladium complex (PdL) based on a thiosemicarbazone ligand. X‐ray diffraction data collected on single crystals reveal that the complex is a neutral mononuclear entity with symmetric square‐planar geometry around the metal center. The complex exhibits an electrocatalytic behavior for proton reduction in DMF solvent using trifluoroacetic acid (TFA) as a proton source. Gas analysis under controlled electrocatalytic conditions during 4 h at a pool mercury working electrode showed a moderate production of dihydrogen. By combining experimental techniques to theoretical calculations, the results are analyzed and compared to those obtained for the previously reported NiL complex in an effort to rationalize the influence of the metal center on the catalytic performance of PdL to mediate hydrogen evolution. [ABSTRACT FROM AUTHOR]