Boehmite nanoparticles, with high surface area and high degree of surface hydroxyl groups, were prepared via hydrothermal-assisted sol-gel processing of aluminium 2-butoxide. The produced powder was covalently functionalized with 3-(trimethoxysilyl)propylamine, and then, in order to support vanadium oxosulfate and molybdenum hexacarbonyl complexes, all the terminal amine groups were changed to Schiff bases by refluxing with salicylaldehyde. These catalysts were applied in the epoxidation of cis-cyclooctene and other olefins with tert-BuOOH in CCl 4 . The catalytic procedures for both catalysts were optimized for various parameters such as solvent and oxidant. Recycling experiments revealed that these heterogeneous nano-catalysts could be repeatedly applied for the epoxidation of alkenes.

Boehmite nano‐particles with a high degree of surface hydroxyl groups were covalently functionalized by 3‐(trimethoxysilyl)‐propylamine to support H3[PMo12O40], H3[PW12O40], H4[SiMo12O40] and H4[SiW12O40] Keggin‐type heteropolyacids. After characterization of these catalysts by FT‐IR, powder X‐ray diffraction, TG/differential thermal analysis, CHN, inductively coupled plasma and transmission electron microscopy techniques, they were applied to the epoxidation of cis‐cycloocten. The progress of the reactions was investigated by gas–liquid chromatography, and the catalytic procedures were optimized for the parameters involved, such as the solvent and oxidant. The results showed that 25 mg of supported H3[PMo12O40] catalyst in 1 ml C2H4Cl2 with 0.5 mmol cyclooctene and 1 mmol tert‐butylhydroperoxide at reflux temperature gave 98% yield over 15 min. Recycling experiments revealed that these nanocatalysts could be repeatedly applied up to five times for a nearly complete epoxidation of cis‐cycloocten. The optimized experimental conditions were also used successfully for the epoxidation of some other alkenes, such as cyclohexene, styrene and α‐methyl styrene.

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