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Modified SBA-15 as an Efficient Environmentally Friendly Nanocatalyst for One-Pot Synthesis of Tetrahydrobenzo[b]pyrane Derivatives

SBA-15 mesoporous silicas modified with proline and aminopropyl functional groups were employed for synthesis of tetrahydrobenzo[b]pyrane derivatives by simply mixing the precursors with surface-modified catalyst in a mortar. The mesoporous catalysts were characterized by Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), small-angle x-ray diffractometry (SAXS), thermogravimetric/differential thermal analyzer (TG/DTA), Barrett–Joiner–Halenda (BJH) pore size and volume analysis, and Brunauer–Emmett–Teller (BET) surface area measurement methods. The results indicate that SBA-15 mesoporous silica modified with proline and aminopropyl functional groups can be effectively utilized for synthesis of tetrahydrobenzo[b]pyrane derivatives.