Silver nanoparticles embedded over mesoporous organic polymer as highly efficient and reusable nanocatalyst for the reduction of nitroarenes and aerobic oxidative esterification of alcohols

Cobalt modified two-dimensional polypyrrole synthesized in a flat nanoreactor for the catalysis of oxygen reduction

“…phthalocyanine (Komissar and Levin, 1964;Zhu and Barat, 2014), triallylamine (Salam et al, 2014)) and a chelated transition metal ion (e.g. Fe, Co), are one of promising Ptalterative catalysts for the ORR (Smirnova et al, 2009).…”

A Highly Water‐Dispersible/Magnetically Separable Palladium Catalyst: Selective Transfer Hydrogenation or Direct Reductive N‐Formylation of Nitroarenes in Water

“…Also, we observed that, under optimizedr eaction conditions, meta-substituted nitroarenes containing either electron-donating or -withdrawingg roups) afforded the corresponding products in quantitative conversion and 71-100 % selectivities (Table3,e ntries 9-11). Then, the sterica nd electronic effects of ortho substituents on the reduction of the nitro group by employing various O-substitutedn itrobenzene derivatives as substrates were explored.I nterestingly,t he re-sults showed that our catalytic system wasv ery successful for av ariety of monosubstituted O-nitrobenzenes:7 5-100 %c onversion and 70-100 %s electivities within 15-20 hb yu sing as little as 0.5 mol %c atalyst and 4equivalents of HCOONH 4 ( Table 3, entries [12][13][14][15][16].E ncouraged by these promising results, we then attempted to investigate the reduction of more sterically demanding 1,3-dimethyl-2-nitrobenzene. Although under (Table 3, entry 17), increasing the catalystl oading to 1mol %w ith 8equivalents of ammonium formate resulted in an improved yield of 55 %w ith excellent selectivity (Table3,e ntry 18).…”

“…Because heterogeneous catalysis has more advantages over homogeneous catalysis from practical, environmental, and economical viewpoints, more attention has been paid to the transfer hydrogenationo f nitroarenes based on recyclable heterogeneous catalysts. In this context,awide variety of solid supports, such as mesocellular foam, [12] mesoporousp olymers, [13] mesoporousC eO 2 , [14] carbon materials, [15] montmorillonite clay, [16] andz eolites, [17] have been employed to immobilize various metal catalysts, including palladium, silver,c opper,r uthenium, and gold, to promote the transfer hydrogenation of nitro groups by using different sustainable hydrogen donors. The main goals of these supported catalysts are to simplify catalyst recycling, minimize the loss of catalyst, and avoid product contamination during repeatedr eactions.…”

Chloride‐Induced Highly Active Au Catalyst for Methyl Esterification of Alcohols

“…The catalytic mechanism of methyl esterification of alcohols is as follows: First, the alcohol molecules were adsorbed on the support surface to weaken the O-H bonds of the alcohols. [35] The α-H was attracted by the O 2 activated on the Au NPs surface. Then, the α-H was removed, forming an oxygen-carbon double bond.…”