Transition metal catalysts play an important role for synthesis of industrially and laboratory important organic fine chemicals to control the selectivity, activity and stability. In this review, we focus on mainly transition metal based supported catalyst, mainly oxide supported catalyst for heterogeneous catalytic hydrogenation and oxidation of some synthetically important organic molecules. First we discuss the industrially important catalytic organic synthetic reactions. This is followed by the role of supported metal catalysts in the heterogeneous synthetic catalytic reactions with specific attention to hydrogenation and oxidation of organic molecules. The role of base metals and noble metals in monometallic and bimetallic catalysts are then discussed. Some synthetic routes for preparation of oxide supported metal catalysts are also discussed. Finally, a general discussion of the metal-support interaction (MSI) in oxide supported metal catalysts is made.

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In this present work, the pristine and the different percentages of co-doped NiO nanoparticles have been successfully synthesized through the sol-gel method. The X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), UV-Visible spectroscopy (UV-Vis), Fourier Transform Infra-Red Spectroscopy (FT-IR), and Vibrating Sample Magnetometer (VSM) were used to study the structural, morphological, optical, functional, and magnetic properties of the synthesized materials. The XRD patterns confirmed the formation of cubic phased NiO with their crystallite size, microstrain, dislocation density was estimated, and the average crystallite size increased with co-dopant inclusion. By introducing the co-dopant proportion in NiO lattice, the intensity of optical absorption was found to increase and the optical bandgap decreased from (E g = 3.6, 3.54, 3.50 eV) due to quantum size effect. SEM result exhibits that the particles are spherical-shaped morphology. The VSM examination shows the magnetic transition of soft to hard-ferromagnetism in room temperature on Zn, Mn codopant ions occupying Ni translational symmetry.

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The liquid-phase catalytic oxidation of cyclohexene to produce cyclohexenol and cyclohexenone directly was attempted using Mn ion substituted in ceria in acetonitrile solvent with 30% H2O2 as oxidant under atmospheric pressure. Structural studies by XRD show indication of ionically dispersed metal over ceria. Among all the catalysts studied, the Mn0.05Ce0.95O2−δ catalyst prepared by the solution combustion method has shown more activity (95.3% conversion with 98.7% selectivity) than others. The influences of the amount of Mn loading, temperature, time, the concentration of H2O2 and solvent have also been investigated. The enhancement of activity in Mn2+ ion substituted ceria as compared to other catalysts has been attributed to Mn–O–Ce ionic interaction in the combustion synthesized catalyst. Ionic substitution also helps to get an active stable catalyst with lower risk of Mn-leaching compared to the impregnated catalyst.