Abstract
Solid acid catalysts facilitate many organic reactions, Cesium salt of tungstophosphoric acid (CsPW) exhibits excellent catalytic activity due to its safety, efficiency, strong acidity, cost-effectiveness and being water tolerant. CsPW has provided promising results under aqueous conditions with the high catalytic efficiency for the synthesis of target 1,3,4-oxadiazoles. The prepared catalyst was fully characterized by FT-IR, X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDAX) and X-ray photoelectron spectroscopy (XPS). 1,3,4-oxadiazoles synthesis is an environmentally friendly, clean and safe synthetic process in short reaction time, simple workup, excellent yield and catalytic recovery. The best yield results (94%) were obtained using cesium tungstophosphoric acid catalyst by model compound in just 40 min. In addition, thermodynamic and kinetic model reaction analysis was also conducted at a temperature range of 298–323 K under the influence of the catalyst. The reaction under kinetic analysis was found to be more regulated than thermodynamic, which may be attributed to the influence of the optimum amount of catalyst being used.
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•We explore the effect of cesium doped tungstophosphoric acid (Cs PW) for the synthesis of series of oxadiazole in water for the first time.•CsPW exhibits excellent yield (up to 94%) devoid of loss of catalytic activity even after four runs.•CsPW showed feasible mechanism to get target oxadiazole.•CsPW, a solid acid catalyst could be hope for the synthesis of other azole moiety.