Functionalized Silica Matrices and Palladium: A Versatile Heterogeneous Catalyst for Suzuki, Heck, and Sonogashira Reactions

Remarkable developments have been accomplished in silica-supported palladium nanoparticles (PdNPs)-mediated organic transformations for the generation of Suzuki (C-C), Heck (C=C), and Sonogashira (C equivalent to C) coupling reactions in academic as well as industrial communities. Various synthetic methods were adopted to prepare highly dispersed PdNPs encapsulated within various forms of silica supports. The type of reaction examined size and shape, stability, and recycling ability of silica-supported PdNPs, and the influence of different reaction parameters on carbon-carbon bond-forming reactions are discussed. In these reactions, the silica-supported PdNPs exhibited superior performances compared to their unsupported colloidal metal nanoparticles (MNPs), revealing the advantages of designing nanocatalysts. Recent progress in the synthesis, catalytic results, stability, and recycling possibilities of silica-supported PdNPs are discussed, along with the prospective outlook of relevant research fields.