An efficient method for the synthesis of 5-substituted-1H-tetrazoles through the reaction of nitriles with sodium azide using titanium oxide–supported boric acid (TiO2-H3BO3) catalyst was reported. The reactions were carried out at 120 °C and provided the corresponding tetrazoles in good to excellent yields. This method displayed significant advantages such as stability of the catalyst, high product yield, simple methodology, and easy work up. Also, this catalyst can be reused several times without loss of its catalytic activity. The aromatic nitriles with electron-donating and electron-withdrawing groups could be accomplished. The structural characteristics of the catalyst were identified by FT-IR, powder X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and inductively coupled plasma (ICP) analyses. پرونده مقاله

5-Substituted-1H-tetrazoles were synthesized by the [3 + 2] cycloaddition of sodium azide with various nitriles in the presence of nickel zirconium phosphate (NiZrP) as an effective heterogeneous catalyst in dimethylsulfoxide at 120 °C. This method has the advantages of good to high yields, simple methodology and easy work-up. The catalyst can be recovered by centrifuging and reused with good yields. There is no appreciable loss of catalytic activity up to five cycles. All aromatic nitriles with electron-donating group could be accomplished as well as that with electron-withdrawing groups. The structural characteristics of the catalyst are identified by scanning electron microscopy (SEM) and XRD instruments. پرونده مقاله