Preparation and characterization of Fe3O4@Boehmite core‐shell nanoparticles to support molybdenum or vanadium complexes for catalytic epoxidation of alkenes

• Published in: Applied organometallic chemistry Vol. 33; no. 4
• Main Authors: Mirzaee, Mahdi, Bahramian, Bahram, Gholampour, Parichehr, Teymouri, Samaneh, Khorsand, Toktam
• Format: Journal Article
• Language: English
• Published: Chichester Wiley Subscription Services, Inc 01.04.2019
• Subjects: alkene epoxidation; Alkenes; Aluminum; Boehmite; Carbonyls; Catalysis; Catalysts; Chemistry; Chlorine compounds; Core-shell particles; Epoxidation; Fe3O4@Boehmite Core‐shell nanoparticles; heterogeneous catalyst; Hexa‐carbonyl molybdenum; Imidazole; Iron oxides; Liquid chromatography; Molybdenum; Nanoparticles; Oxo‐sulfato vanadium (IV); Sol-gel processes; Vanadium
• ISSN: 0268-2605; 1099-0739
• DOI: 10.1002/aoc.4792

Fe3O4 core nanoparticles were prepared via a solvothermal process, and then they were covered with a surface hydroxyl‐rich boehmite shell via the hydrothermal‐assisted sol–gel processing of aluminum 2‐propoxide. The outer surface of the boehmite shell was subsequently covalently functionalized with 3‐(tri‐methoxysilyl)‐propylamine or 3‐(tri‐methoxysilyl)‐propyl chloride, and the terminal chlorine groups were treated with imidazole. These compounds were used to support the hexa‐carbonyl molybdenum and oxo‐sulfato vanadium (IV) complexes. The supported catalysts were characterized by the FT‐IR, CHN, ICP, and TEM analysis techniques. They were then used in the epoxidation of cis‐cyclooctene. The catalytic procedures were optimized for different parameters such as the solvent, oxidant, and temperature. The reaction progress was investigated by the gas–liquid chromatography analysis. The catalysts used were simply recovered from the solution by applying a magnet, and recycling the experiments revealed that the heterogeneous nanocatalysts could be repeatedly used for the epoxidation of cis‐cyclooctene. The optimized conditions were also successfully used for the epoxidation of some other alkenes. Fe3O4 core nano‐particles were prepared via solvothermal process and then covered hydrothermally with boehmite shell. The produced powder was covalently functionalized with different amine groups and was used to support vanadium or molybdenum complexes. These catalysts were applied in epoxidation of cis‐cyclooctene and the catalytic procedures were optimized for different parameters such as solvent, oxidant and temperature.