We describe the synthesis of a novel Fe 3 O 4 /amidoxime (AO)/Pd nanocatalyst by grafting of AO groups on Fe 3 O 4 nanoparticles and subsequent deposition of Pd nanoparticles. Prior to grafting of AO, the 2-cyanoethyl-functionalized Fe 3 O 4 nanoparticles prepared through combining 2-cyanoethyltriethoxysilane and Fe 3 O 4 were treated with hydroxylamine. The AO-grafted Fe 3 O 4 nanoparticles were then used as a platform for the deposition of Pd nanoparticles. The catalyst was characterized using Fourier transform infrared spectroscopy, X-ray diffraction, scanning and transmission electron microscopies, vibrating sample magnetometry, wavelength-and energy-dispersive X-ray spectroscopies and inductively coupled plasma analysis. Fe 3 O 4 /AO/Pd is novel phosphine-free recyclable heterogeneous catalyst for Sonogashira reactions. Interestingly, the novel catalyst could be recovered in a facile manner from the reaction mixture by applying an external magnet device and recycled seven times without any significant loss in activity.Fe 3 O 4 /AO/Pd as an effective nano catalyst in the sonogashira reaction

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Nanoscale graphene oxide sheets (NGO), as activated carbocatalysts, were synthesized by a reduction size strategy and used in chemoselective oxidative conversion of benzylic C−H to the corresponding carboxylic acid. On the basis of the results of the optimization process of different parameters, 3 equiv of H 2 O 2 for each C−H group, 100 wt % of NGO in aqueous medium, acetone as a cosolvent, and a reaction temperature of 100 °C were selected as optimum parameters. In this optimum condition, xylenes and toluene over 24 h with good yield were converted to the corresponding carboxylic acid, and in the case of diphenylmethane and ethylbenzene, these substrates with excellent yield were converted to benzophenone and acetophenone.

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