Immobilization of MoO۲(acac)۲ on Multiwall Carbon Nano Tube and Epoxidation of Alkenes

The acidic group (-CO۲H) of MultiWall Carbon Nanotube (MWCNT) converted to acyl chloride group (-COCl) producing of MVCNT@COCl. Then the reaction of MVCNT@COCl and MoO۲(acac)۲ resulted in direct immobilization of the MoO۲(acac)۲ and the formation of MVCNT@CO(acac)MoO۲(acac) catalyst. In addition, the MVCNT@COCl was esterified by NaOC۲H۵ and formed the esteric MVCNT@COC۲H۵ reagent. In a subsequent reaction of MVCNT@COC۲H۵ by ethylene diamine, the MVCNT@CONHCH۲CH۲NH۲ was produced. It was reacted with MoO۲(acac)۲ and immobilized the MoO۲(acac)۲ via imine bond formation and produced the MVCNT@CONHCH۲CH۲N(acac)MoO۲(acac) catalyst. The functionalized MVCNT reagents were characterized by FT-IR spectra and elemental analysis. The molybdenum loading on MVCNT was determined by ICP analysis. The catalytic activity of the two molybdenum immobilized catalysts (MVCNT@COMoO۲(acac)۲ and MVCNT@CONHCH۲CH۲N(acac)MoO۲(acac)) was investigated in the epoxidation of cyclooctene and different reaction parameters such as solvent, oxidant, amount of catalyst and oxidant were optimized and the epoxidation of different alkenes was investigated in these optimized conditions. The obtained results showed that the supported catalysts of MVCNT@CO(acac)MoO۲(acac)۲ and MVCNT@CONHCH۲CH۲N(acac)MoO۲(acac) were highly active and selective in the epoxidation of a wide range of alkenes. The reusability of the supported catalysts was also studied. The results showed that they had good reusability in the epoxidation of alkenes.

کلیدواژه ها:

carbon nano tube ، Immobilization ، Mo ، Epoxidation ، alkene