The First Example of <i>ortho</i>-Arylation of Benzamides over Pd/Mesoporous Silica: A Novel Approach for Direct sp² C–H Bond Activation

Three-dimensional mesoporous silica with a highly dispersed palladium nanoparticles composite (PS-3) catalyst has been prepared and characterized by X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, nitrogen sorption, and high resolution transmission electron microscopy. The PS-3 catalyst utilized for the first time as an efficient and reusable catalyst in the <i>ortho</i>-arylation of benzamides by aryl iodides has been demonstrated with the simplest amide CONH₂ as a directing group. It can be successfully applied to various benzamides and aryl iodides with both electron donating and withdrawing groups. The catalyst can be simply recovered and reused several times without significant loss in catalytic activity

SnO₂–SiO₂ Mesoporous Composite: A Very Active Catalyst for Regioselective Synthesis of Aromatic Ketones with Unusual Catalytic Behavior

Aromatic ketones (R-Ar-CO-R′) have been prepared directly through C–C bond formation using aromatics, aryl, and alkyl acid halides in a Friedel–Crafts reaction over a reusable and catalytically active ordered SnO₂–SiO₂ three-dimensional mesoporous composite (PS-4) catalyst, which was found to be superior to modified zeolites, functionalized MCM-41, and supported heteropolyacid catalysts