Ultrathin γ-Fe2O3 nanosheets as a highly efficient catalyst for the chemoselective hydrogenation of nitroaromatic compounds

Enhanced Stability and Catalytic Activity of a Nanocatalyst with Reusable Ionic Liquid Hydrogels for the Reduction of Organic Pollutants

Nitroaromatic compounds have a wide range of applications. However, they pose a significant threat to both the environment and human health. Ionic liquid hydrogels (ILs-gels) have emerged as a cost-effective and environmentally friendly option for various applications. However, conventional ILs-gels are known to possess mechanical flaws or defects. The procedure utilized a facile synthesis route that involved the polymerization of acrylamide (AM) and ionic liquids (ILs) to create a novel candidate for nanoparticle absorption. This study resolved this issue by creating toughened hydrophobic combined hydrogels synthesized through the addition of SiO2@poly(butyl acrylate) core-shell inorganic-organic hybrid latex particles (SiO2@PBA) to the AM-ILs mixture. The SiO2@PBA particles were chosen to provide the hydrogels with exceptional stretchability (up to 4050% strain) and high mechanical properties (tensile strength of 126 kPa) by acting as both a nanotoughener and a cross-linking point for hydrophobic linkage. Additionally, the P(AM/ILs)-SiO2@PBA hydrogel served as a template for the in situ and stable formation of palladium (Pd) nanoparticles. By incorporation of these Pd nanoparticles as catalysts into P(AM/ILs)-SiO2@PBA hydrogel carriers, the resulting P(AM/ILs)-SiO2@PBA/Pd hydrogels exhibited the ability to catalyze the degradation of p-nitrophenol. Remarkably, even after 15 applications, the efficiency of the degradation process remained consistently above 90%. Thus, the innovative SiO2@PBA toughened ILs-hydrogel design strategy can be utilized to develop robust and stretchable hydrogel materials for catalytic use in the sewage disposal industry.

Selective Nitro Reduction of Ester Substituted Nitroarenes by NaBH4-FeCl2

This work aimed to explore a novel protocol for selective reduction of the nitro group on the aromatic ring while remaining the ester group unaffected. In this study, NaBH4-FeCl2 was disclosed as a key reductant in the process. NaBH4-FeCl2-mediated reduction showed high chemoselectivity, gave the desired products in magnificent yield (up to 96%), and was applied to synthesize a key intermediate of vilazodone (an antidepressant drug) on a hectogram scale in a total yield of 81% (two steps). The protocol is practical, and capable of synthesis of a range of aromatic amines, especially those with ester substituted in the ring.

1T-MoS2 catalysed reduction of nitroarenes and a one-pot synthesis of imines

An expedient synthesis of aromatic amines and imines via the reduction of nitroaromatics using 1T-MoS2 as a heterogeneous catalyst.

Fabrication of magnetically separable ruthenium nanoparticles decorated on channelled silica microspheres: Efficient catalysts for chemoselective hydrogenation of nitroarenes

Fe₃O₄-SiO₂ microspheres were synthesized by a three-step synthetic procedure involving silica coating, surface capping, and surface modification. These magnetic mesoporous microspheres were employed as sorbents for the incorporation of ultrasmall Ru nanoparticles (2-5 nm) followed by thermal aggregation of the microspheres for achieving better heterogeneity and low leaching. The Ru decorated Fe₃O₄-SiO₂ microspheres (Ru@Fe₃O₄-CSM) were applied as chemoselective catalysts to convert more than 20 substituted nitroarenes to corresponding amines with good-to-excellent conversion (77-99%) and selectivity (70-100%) under mild conditions; the catalyst can be magnetically recovered within a frame of 90s (recovery time-lapse) and reused up to 5 times without significant decrease in activity or selectivity. Magnetic hysteresis studies were performed to elucidate the magnetic behavior of the ruthenium decorated materials.

High electrochemical performance of Fe2O3@OMC for lithium-ions batteries

Fe₂O₃@OMC (ordered mesoporous carbon) is synthesized using Fe-MOFs (metal-organic frameworks). The Fe₂O₃@OMC pore size is mostly concentrated at approximately 2-4 nm. Compared to traditional OMC or carbonized Fe-MOFs, Fe₂O₃@OMC demonstrates a higher capacity (the capacity remains at 1176.6 mAh g^-1 after 500 cycles under a current density of 0.1 A g^-1) and a longer cycle life. The first cycle capacity of Fe₂O₃@OMC is ultrahigh at 2448.6 mAh g^-1, and the reversible capacity is 1294.1 mAh g^-1. Fe₂O₃@OMC maintains a good performance under current densities of 0.1 A g^-1, 0.2 A g^-1, 0.5 A g^-1, 1 A g^-1, 2 A g^-1, and 5 A g^-1, with electric capacities of 1100.8 mAh g^-1, 1017.6 mAh g^-1, 849.3 mAh g^-1, 690.7 mAh g^-1, 506.7 mAh g^-1, and 272.1 mAh g^-1, respectively. Thus, the material has good rate performance. Combining iron oxide and MOFs is helpful to improve the capacity performance.

Ruthenium nanoparticles supported on nitrogen-doped porous carbon as a highly efficient catalyst for hydrogen evolution from ammonia borane

The two-dimensional magnetic NC-Fe materials were prepared and modified with Ru nanoparticles to form Ru/NC-Fe nanocatalyst with excellent catalytic activity for hydrogen evolution from ammonia borane.

Reduction of Nitro Compounds Using 3d-Non-Noble Metal Catalysts

The reduction of nitro compounds to the corresponding amines is one of the most utilized catalytic processes in the fine and bulk chemical industry. The latest development of catalysts with cheap metals like Fe, Co, Ni, and Cu has led to their tremendous achievements over the last years prompting their greater application as "standard" catalysts. In this review, we will comprehensively discuss the use of homogeneous and heterogeneous catalysts based on non-noble 3d-metals for the reduction of nitro compounds using various reductants. The different systems will be revised considering both the catalytic performances and synthetic aspects highlighting also their advantages and disadvantages.