Copper supported on polymer-coated magnetic nanoparticles was designed and synthesized as a separable heterogeneous catalyst. The catalyst was fully characterized using several techniques such as Fourier transform infrared and energy-dispersive X-ray spectroscopies, scanning and transmission electron microscopies, X-ray diffraction, vibrating sample magnetometry, thermogravimetric analysis and inductively coupled plasma atomic emission spectrometry. All results showed that copper was successfully supported on the polymer-coated magnetic nanoparticles. Also, results showed that the synthesized material can be used as an efficient catalyst for the preparation of a series of 1,4-disubstituted 1,2,3-triazoles from corresponding halides, alkynes and sodium azide. The catalyst can be easily isolated from the reaction solution by applying an external magnet and reused for nine runs without any significant loss of catalytic activity.

Carboxyl functionalized graphene quantum dots (CGQDs) was applied as a highly efficient and green acidic catalyst for the coupling reaction of 2-naphthole and benzaldehyde derivatives for the preparation of 14H-dibenzo xanthene derivatives, under solvent-free microwave irradiation conditions. The structures of the 14H-dibenzo xanthene derivatives were confirmed by FT-IR, 1 H-NMR and 13 C-NMR spectroscopic techniques. The structure of catalyst was also confirmed by FT-IR, XRD, TEM and PL techniques. In order to demonstrate the positive impact of CGQDs catalyst, the reaction times and yields of the products were compared with similar products which have been reported previously. 14H-Dibenzo xanthene derivatives were synthesized in simple procedure, good to excellent yields via the present procedure.

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N,N-Disubstituted hydroxylamines were prepared directly from secondary amines by a reliable method using an oxidizing task-specific ionic liquid, choline peroxydisulfate. The operational simplicity, high selectivity, and green reaction conditions, make this method efficient and practical.

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