Palladium Nanoparticle Loaded Bifunctional Silica Hybrid Material: Preparation and Applications as Catalyst in Hydrogenation Reactions

Abstract

Bifunctional mesoporous silica was prepared by co-condensation of tetraethyl orthosilicate (TEOS) with functionalized organosilanes containing azides or alkoxyamines. Orthogonal functional groups at the particles were selectively addressed in subsequent chemical modifications through "click"-chemistry ("click to ligand" strategy) and radical nitroxide exchange. Palladation with PdCl delivered Pd nanoparticle-loaded silica material bearing sulfoxides and additional aminoamides as stabilizing ligands by means of in situ reduction of the Pd -salt. These functional particles were successfully applied to the hydrogenation of alkynes and alkenes. Aldehyde hydrodeoxygenation and benzyl ether cleavage were achieved with these hybrid catalysts under mild conditions. Particles were analyzed by IR, TEM/STEM, EDX, and solid-state NMR spectroscopy.

Synthetic Organic Transformations of Transition‐Metal Nanoparticles as Propitious Catalysts: A Review

“…Eckert and Studer reported the synthesis of Pd based bifunctional mesoporous silica nanoparticles bearing stabilizing ligands such as sulfoxides and amino amides (Scheme 22 and 23). [24] The hybrid catalysts were analyzed by IR, TEM/STEM, EDX, and solid-state NMR experiments. The semi-hydrogenation reaction with alkynes and benzyl ethers not only fetched alkenes but also hydrodeoxygenation products.…”

Direct Sulfoxidation of Aromatic Methyl Thioethers with Aryl Halides by Copper-Catalyzed C(sp3)–H Bond Activation

“…Benzylsulfoxide derivatives are the most privileged scaffolds in natural biological products [1], pharmaceutical chemistry [2], and functionalized materials [3]. In particular, benzylsulfoxide derivatives exhibit a wide range of biological properties, such as anti-bacterial activity (Scheme 1I) [4], anti-cancer activity (Scheme 1II) [5], and HIV inhibition (Scheme 1III) [6].…”

“…The activation of the C-H bond is considered as one of the most useful C-C bond formation strategies [10]. However, many studies have demonstrated that, compared with the C(sp 2 )-H bond functionalization reactions, the application of C(sp 3 )-H bond functionalization reactions remains a challenge in this field [11], as the reactions of C(sp 3 )-H bond functionalization require harsher conditions and activated systems [12]. Given the present challenges, the development of more efficient and environmentally-friendly chemical processes for drug discovery is required [13].…”

“…Given the present challenges, the development of more efficient and environmentally-friendly chemical processes for drug discovery is required [13]. Herein, we report on a novel copper-catalyzed direct sulfoxidation reaction by the activation of the C(sp 3 )-H bond (Scheme 2C). This method can provide a simple and convenient route to biologically-active benzylsulfinylbenzene compounds.…”

Effect of Fe3O4 particles on multi-hollow morphology of poly(HEMA-divinylbenzene-styrene) microspheres prepared by Pickering suspension polymerization

“…Furthermore, the magnetic properties provided by magnetite particles often make the separation and recyclability of resulting catalysts much easier. The catalysts based on magnetic particles were efficient in many chemical transformations catalyzed by transition metals, for instance, in the reactions of oxidation [31,32] and epoxidation [33,34], hydrogenation [35,36] and hydroformylation [37,38], and also in olefin metathesis [26,39] and carbon-carbon coupling [40][41][42][43] reactions. Magnetically separable organocatalysts were also prepared based on the particles of magnetite [25,30].…”