Mn₃O₄-Nanoparticles Fastened Nitrogen-Rich Porous Organic Material as a Hybrid Nanocatalyst for the Selective...

Developing novel, inexpensive and reusable hybrid nanocatalyst for the selective conversion of alcohols to valuable intermediates is very challenging, not only from the perspectives of organic synthesis, but also for meeting the demands of the fine chemical and pharmaceutical industries. Here we report a facile process for fabricating Mn₃O₄-nanoparticles over the surfaces of a nitrogen-rich porous organic polymer with flower-like morphology (Mn₃O₄-NPs@PCNF). The electron microscopic analysis reveals the 3D-flower-like morphology, interweaving, and slight bending of nanoflakes. The powder XRD data confirmed the integration of crystalline Mn₃O₄-NPs. BET surface areas and pore volumes were 645 and 330 m²g^-1 and 0.62 and 0.25 cm³g^-1 for the support and Mn₃O₄-NPs@PCNF hybrid catalyst, respectively. Large specific surface area, bimodal pores, and 3D nanoflower architecture enable uniform dispersion of Mn₃O₄-NPs, while nitrogen-rich functionality stabilizes and acts as a capping agent in restricting further expansion. The material showed high catalytic activity for the selective oxidation of primary and secondary alcohols in the presence of TBHP as an oxidant. It showed 98% conversion within 10 h with a high turnover number (TON) of 368 for the selective oxidation of 1-phenylethanol. The Mn₃O₄-NPs facilitate reaction, while bimodal pores of nanoscale dimensions enable facile diffusion of reactants and products.