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چکیده
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Selective oxidation of alcohols to carbonyl compounds is one of the most important and challenging reaction in organic chemistry [1, 2]. Although a wide variety of reagent systems are available for this key transformation and the major disadvantages of these methods include removal or recovery of the expensive catalyst, metal residues in the products, and the formation of large amounts of toxic waste. Hence there is a need to develop new catalysts which can overcome these drawbacks. Magnetic nanoparticle-based materials (MNPs) are ideal supports for the immobilization of catalysts, since they can be recollected by using an external magnet [3]. In continuation of our studies on magnetically separable catalysts in organic reactions [4], herein, we report oxo-vanadium ephedrine complex supported on magnetic nanoparticles [VO(ephedrine)@MNPs] as a reusable organic-inorganic hybrid catalyst for the selective oxidation of primary and secondary alcohols to the corresponding aldehydes and ketones using TBHP as an oxidant in PEG at 80 oC. In summary, two major advantages of this method are: (1) the preparation and separation of VO(ephedrine)@MNPs is simple (2) VO(ephedrine)@MNPs is reused for several times (10 runs) with little loss of activity.
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