Aminal‐based Hypercrosslinked Polymer Modified with Small Palladium Nanoparticles for Efficiently Catalytic Reduction of Nitroarenes

Abstract

Fabrication of heterogeneous catalysts with excellent activity, selectivity and stability is significant for various catalytic applications. Here, we prepared a hypercrosslinked polymer (HCP) via a facile and cost‐effective strategy using ferrocenecarboxaldehyde and melamine as building blocks. Then, the HCP was modified with highly dispersed ultrafine Pd nanoparticles (Pd/HCP). The obtained Pd/HCP shows excellent catalytic activity in the catalytic reduction of nitroarenes under mild reaction conditions. It′s worth mentioning that the N atoms in the HCP can efficiently coordinate Pd ions to form small Pd nanoparticles (NPs) and subsequently prevent the aggregation and leaching of Pd NPs during the reaction, so the Pd/HCP catalyst is highly stable and can be reused at least eight cycles without loss of catalytic activity. Therefore, this work may provide possibilities for using HCPs as ideal supporting materials for fabricating highly stable and efficient heterogeneous catalysts.

Controlled growth of ultrafine metal nanoparticles mediated by solid supports

“…92 Dong et al prepared thiol-containing HCPs using ferrocenecarboxaldehyde and melamine as building blocks, which were loaded with Pd UMNPs (2.89 nm). 93 The resulting Pd UMNPs@HCPs composites showed excellent activity and stability in the catalytic reduction of nitroarenes. Tan et al reported a series of Au UMNPs (range of 1.7 -5.1 nm) supported on a HCP (Figure 12b).…”

Palladium nanoparticles embedded in mesoporous carbons as efficient, green and reusable catalysts for mild hydrogenations of nitroarenes

“…Finally, changing the nature of the solvent was unsuccessful since low yields were observed in iPrOH or propane-1,2-diol and no reaction was observed in H 2 O (entries 9-11). It can be pointed out that, compared to numerous catalysts and reducing agents described, [15][16][17][18] both IM1 and IM2 allowed a chemospecic reduction of the nitro group (the acetyl remaining unchanged) and avoided the necessity of high H 2 pressure. Interestingly, performing the hydrogenation in the presence of a commercially available Pd/C or of Pd Encat NP30 catalyst afforded 1a in much lower yields (entries 12 and 13) conrming therefore the high activity of IM2.…”

A Combined Mechanochemical and Calcination Route to Mixed Cobalt Oxides for the Selective Catalytic Reduction of Nitrophenols

“…To investigate applicability of our catalyst in a flow process [116][117][118][119][120], we simulated a flow reactor with a simple proof-of-concept model. Catalyst Co@350 was loaded onto two 0.22 µm nylon syringe filters; 8 mg in filter (i) and 4 mg in filter (ii), then stacked sequentially ( Figure 8A).…”