Magnetic Iron nanoparticles grafted with Schiff base and Schiff-base Sn complexes for application in catalysis

Abstract

Introduction: Modified Fe₃O₄ nanoparticles display selective catalytic activity with less tedious experimental procedures under mild reaction conditions (1). Difficulty in product separation and use of harsh parameters, in the catalytic conversion of anthracene to industrially important 9,10 anthraquinone is becoming significant challenge in the field of catalysis (2). In the present study, novel Fe₃O₄@SB@Sn system was explored in order to address the existing crucial challenges in the catalytic oxidation of anthracene.

Methods: The Co-precipitation method was employed for the synthesis of bare Fe₃O₄ nanoparticles. The modified heterogeneous system was developed by sequential coating with Schiff base (SB) and (CH₃)₂SnO.    

Results &Discussions: Fig. 1(a) illustrate the additional peaks corresponding to C=N. C=O and C-C bond stretching’s after the attachment of SB on the surface of Fe₃O₄ nanoparticles (3). Fig. 1(b) represents the TGA plot, which indicates the enhanced thermal stability of final catalyst. Various catalytic parameters including different catalyst, concentration of H₂O₂ (Oxidant), temperature were tested for this particular reaction and given in Fig. 1(c).

Conclusions: The novel and re-usable catalytic system Fe₃O₄@SB@Sn produce 9,10 anthraquinone with 100% selectivity and 92.4% conversion (Reaction conditions: 0.5 mmol anthracene, 0.02 mmol catalyst, 10 ml acetonitrile, 3 mmol H₂O₂(oxidant), refluxing at 70 ⁰C for 5 h). Presence of synergic effect of both metals i.e. Fe and Sn is responsible for the enhancement in the catalytic activity of Fe₃O₄@SB@Sn.

Keywords: Fe₃O₄ nanoparticles; Schiff base; catalytic oxidation of Anthracene, 9,10 anthraquinone

Acknowledgment: Manpreet Kaur acknowledge Punjab Engineering college and MHRD for GATE fellowship.

References

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