Enhanced aqueous oxidation activity and durability of simple manganese(iii) salen complex axially anchored to maghemite nanoparticles†
Abstract
Simple Mn-salen complex was anchored coordinatively to γ-Fe2O3 nanoparticles through amine functionality which provide a new magnetically recoverable nanocatalyst with high oxidation activity and stability. Catalyst characterization was performed using FT-IR, UV-Vis, XRD, EDS, TGA and ICP-AES. TEM image revealed a quasi-spherical structure with size smaller than 20 nm for nanocatalyst. A thermal stability up to around 300 °C was verified for prepared nanocatalyst based on thermogravimetric analysis. Finally, the catalytic performance of magnetically recoverable Mn-catalyst was exploited in the green oxidation of different types of functional groups including olefins, alcohols, saturated hydrocarbons and sulfur containing compounds with n-Bu4NHSO5 (TBAOX) in water under heterogeneous conditions. The salen catalyst proved to be reusable for at least eight times and the oxidant's by-product (n-Bu4NHSO4) could also be recycled.