Cross-linked poly (4-vinylpyridine) supported azide ion as a versatile and recyclable polymeric reagent for synthesis of 1-substituted-1H-1,2,3,4-tetrazoles

Cross-linked poly (4-vinylpyridine) supported azide ion, P₄-VP]N₃, is easily prepared and used as an efficient polymeric reagent for synthesis of 1-substituted-1H-1,2,3,4-tetrazoles via condensation reaction of azide ion, primary aromatic amines, and triethyl orthoformate in glacial acetic acid. After optimization of the reaction conditions, a wide variety of primary aromatic amines were also subjected to preparation of the corresponding 1-aryl-1 H-1,2,3,4- tetrazoles using P₄-VP]N₃ under heterogeneous conditions. In this method, the reaction times were very short and the isolated yields were excellent (90–98 %). 1-Aryl-1H-1,2,3,4- tetrazole products were characterized by Fourier transform infrared (FT-IR) and some of them were also characterized by proton nuclear magnetic resonance (¹H NMR) spectroscopy, and physical properties were compared with the literature values of known compounds. The spent polymeric reagent were regenerated quantitatively and reused for several cycles without significant loss of their activity.