Immobilization of a molybdenum complex on the surface of magnetic nanoparticles for the catalytic epoxidation of olefins

• Published in: New journal of chemistry 2016-01, Vol.4 (2), p.158-1586
• Main Authors: Zare, Maryam, Moradi-Shoeili, Zeinab, Bagherzadeh, Mojtaba, Akbayrak, Serdar, Özkar, Saim
• Format: Article
• Language: English
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/c5nj02218e

Novel organic-inorganic hybrid heterogeneous nanocatalysts were obtained by covalent anchoring of a molybdenum( vi ) complex of salicylidene 2-picoloyl hydrazine, MoO 2 (sal-phz)(CH 3 OH), ( 1 ) on the surface of magnetic nanoparticles functionalized by one of two routes: in the first method, the surface of magnetic nanoparticles is directly modified with 3-chloropropyltrimethoxysilane yielding 1A . In the second method, magnetic nanoparticles were silica-coated with tetraethoxysilane and then with 3-chloropropyltrimethoxysilane yielding the intermediate 2B . Then complex 1 was grafted on the surface of 1A or 2B through covalent interaction yielding 2A or 3B , respectively. The nanocatalysts 2A and 3B were characterized by FT-IR, XRD, SEM, TGA, EDX and vibrating sample magnetometry techniques. Nanocomposite 2A shows a much higher catalytic activity and stability in liquid phase epoxidation reactions, with t -BuOOH as the oxidant, compared to that of 3B . Additionally, the results of comparative study show that 2A is more active and reusable than the Mo complex immobilized SBA-15. A molybdenum complex was immobilized on Fe 3 O 4 nanoparticles modified with chloropropyl by two routes and used as a nanocatalyst for the oxidation of alkenes.