Synthesis and characterization of a magnetically recoverable molybdenum(VI) nanocatalyst for eco-friendly oxidation of alcohols

A metal organic framework, UiO-66-NH2, based on a molybdenum Schiff base complex for the efficient electrochemical determination of diphenoxylate

Diphenoxylate, an agonist and opioid agent, is applied to enhance the activity of the circular muscle of the intestine. In this work, we prepared a novel electrochemical sensor for the determination of diphenoxylate based on a modified UiO-66-NH2 metal-organic framework (UiO-66-NH2 MOF) using a molybdenum Schiff base complex and NiS nanoparticles (NiSnp) in a carbon paste electrode (CPE). The UiO-66-NH2 MOF and UiO-66@Schiff-base-Mo were studied through advanced analysis techniques, such as X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX) and transmission electron microscopy (TEM), to reveal the inherent characteristics of the material. The results also showed that the morphology and structure of the UiO-66-NH2 MOF were maintained after surface modification. The electrochemical properties of the proposed modified electrode (NiSnp/MOF@Mo/CPE) were characterized using cyclic voltammetry (CV). Also, a differential pulse voltammetry (DPV) method was employed for diphenoxylate determination with NiSnp/MOF@Mo/CPE. A linear range was achieved from 1.0 to 55.0 μM and 65.0 to 125.0 μM, and the detection limit was found to be 0.34 μM. The capability of the fabricated sensors based on NiSnp/MOF@Mo/CPE was investigated through diphenoxylate determination in real samples.

Catalytic epoxidation of olefins in liquid phase over manganese based magnetic nanoparticles

Epoxidation of olefins stands out as a crucial class of reactions and is of great interest in academic research and industry due to the production of various important fine chemicals and intermediates. Manganese complexes have the potential to catalyze the epoxidation of olefins with high efficiency. Magnetic nanocatalysts have attracted significant attention for immobilizing homogeneous transition metal complexes. Easy separation by external magnetic fields, nontoxicity, and a core shell structure are the main advantages of magnetic nanocatalysts over other heterogeneous catalysts. The method of functionalizing magnetic nanoparticles and of anchoring homogeneous metal complexes has significant effects on catalytic performance. Therefore, a critical review of recent research progress on manganese complexes' immobilization on magnetic nanoparticles for liquid phase olefin epoxidation is necessary. In this work, magnetic nanoparticles are categorized according to their preparation procedures and structures. The physical/chemical properties, catalytic performance for olefin epoxidation, reusability and plausible reaction mechanisms will be discussed, in an attempt to unravel the structure-function relationship and to guide the future study of MNPs' design for olefin epoxidations.