Facile Transfer Hydrogenation of N-Heteroarenes and Nitroarenes Using Magnetically Recoverable Pd@SPIONs Catalyst.

Catalysts with active, selective, and reusable features are desirable for sustainable development. The present investigation involved the synthesis and characterization of bear-surfaced ultrasmall Pd particles (<1 nm) loaded onto the surface of magnetic nanoparticles (8-10 nm). The amount of Pd loading onto the surface of magnetite is recorded as 2.8 wt %. The characterization process covered the utilization of scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), transmission electron microscopy (TEM), inductively coupled plasma (ICP), and X-ray photoelectron spectroscopy (XPS) methods. The Pd@Fe3O4 catalyst has shown remarkable efficacy in the hydrogenation of quinoline, resulting in the production of >99% N-ring hydrogenated (py-THQ) product. Additionally, the catalyst facilitated the conversion of nitroarenes into their corresponding aniline derivatives, where hydrogen was achieved by H2O molecules with the aid of tetrahydroxydiboron (THDB) as an equilibrium supportive at 80 °C in 1 h. The high efficiency of a transfer hydrogenation catalyst is closely related to the metal-support synergistic effect. The broader scope of functional group tolerance is evaluated. The potential mechanism underlying the hydrogenation process has been elucidated through the utilization of isotopic labeling investigations. The application of the heterocyclic compound hydrogenation reaction is extended to formulate the medicinally important tubular polymerization inhibitor drug synthesis. The investigation of the recyclability of Pd@Fe3O4 has been conducted.

Hydrogenation of CO2 into Value-added Chemicals Using Solid-Supported Catalysts.

Reducing CO2 emissions is an urgent global priority. In this context, several mitigation strategies, including CO2 tax and stringent legislation, have been adopted to halt the deterioration of the natural environment. Also, carbon recycling procedures undoubtedly help reduce net emissions into the atmosphere, enhancing sustainability. Utilizing Earth's abundant CO2 to produce high-potential green chemicals and light fuels opens new avenues for the chemical industry. In this context, many attempts have been devoted to converting CO2 as a feedstock into various value-added chemicals, such as CH4 , lower methanol, light olefins, gasoline, and higher hydrocarbons, for numerous applications involving various catalytic reactions. Although several CO2 -conversion methods have been used, including electrochemical, photochemical, and biological approaches, the hydrogenation method allows the reaction to be tuned to produce the targeted compound without significantly altering infrastructure. This review discusses the numerous hydrogenation routes and their challenges, such as catalyst design, operation, and the combined art of structure-activity relationships for the various product formations.

Facile Hydrogenation of Furfural by MOF-Derived Graphitic Carbon Wrapped FeCo Bimetallic Catalysts.

A catalytic system for selective transformation of furfural into biofuel is highly desirable. However, selective hydrogenation of the C=O group over the furan ring of furfural to produce ether in one step is challenging. Here, we report the preparation of a series of magnetically recoverable FeCo@GC nano-alloys (37-40 nm). Fe3 O4 (3-5 nm) and MOF-71 (Co), used as the Co and C source, were mixed together in a range of Fe/Co ratios, and then encapsulated in a graphitic carbon (GC) shell to prepare such alloys. STEM-HAADF shows the darker core made of FeCo and the shell of graphitic carbon. Furfural is hydrogenated to produce >99% isopropyl furfuryl ether in isopropanol with >99% conversion at 170 °C under 40 bars of H2 , whereas n-chain alcohol, such as ethanol, produces corresponding ethyl levulinate in 93%. The synergistic effect due to the charge transfer from Fe to Co leads to higher reactivity of FeCo@GC. The catalyst, which can be separated from the reaction medium using a simple magnet without significant damage to the surface or composition, retained its reactivity and selectivity for up to four consecutive cycles.