Articles
Inorganic Chemistry Communications (13877003)180
This research focuses on the catalytic effect of transition metals substituted Wells-Dawson type polyoxometalates (M-WDPOMs; M = Mn, Fe, Co, Cu, Ni, and Zn) in epoxide ring-opening reactions. These catalysts were chosen for their sustainability, non-toxic nature, availability, low cost, environmental friendliness, and high electron transfer ability. The M-WDPOM compounds were prepared, characterized using various techniques, and their catalytic activities in ring-opening reactions of different epoxides with sodium azide and acetic anhydride were investigated. Azidolysis reactions were performed under reflux in a mixture of acetonitrile and water, while acetolysis reactions were conducted under solvent-free conditions. Among the different M-WDPOM catalysts, Fe-WDPOM demonstrated the highest catalytic performance in these ring-opening reactions with shorter reaction times and higher yields. Consequently, azidoalcohols and diacetates were produced efficiently with high to excellent yields (80–98 %). © 2025 Elsevier B.V.
Catalysis Letters (1572879X)155(2)
A hybrid catalyst based on Mo132 as a Keplerate type polyoxometalate and MimAm as an ionic liquid was used as an effective catalyst for selective epoxidation of different alkenes with H2O2 as a green and safe oxidant. The effects of various parameters such as catalyst, oxidant amounts, reaction time, and temperature were also studied in selective epoxidation of cyclooctene. Moreover, under the optimal reaction conditions, the epoxidation of different alkenes was performed with 54–100% yields. Interestingly, this catalyst complies with the benefits of easy preparation, recovery, recycle, high catalytic activity, simplified workup, and flexible composition. © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024.
Silica-supported polyoxometalates [Si/AlO2]@[PWM] (M = Zn, Cu, Ni, Co, Fe, Mn, and Cr) were produced by immobilizing transition metal substituted Keggin-type polyoxometalates on cationic silica nanoparticles. These silica-supported polyoxometalates were then encapsulated with hexadecyltrimethylammonium bromide to obtain [Si/AlO2]@[PWM]@CTAB (M = Zn, Cu, Ni, Co, Fe, Mn, and Cr) to prevent polyoxometalate leaching. Characterization by FT-IR, TG-DTG, XRD, SEM, and TEM indicated that the polyoxometalate structure was retained after immobilization and encapsulation. These nanoscale compounds were used as heterogeneous catalysts in the oxidation of various alcohols, achieving very good to excellent yields with H2O2 as an oxidant, and demonstrating high reusability. These benefits introduce surfactant-encapsulated silica-supported polyoxometalates as highly efficient heterogeneous catalysts in different oxidation reactions. © 2025 The Royal Society of Chemistry.
