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Novel heterogeneous pyridine immobilised magnetic silica (Fe3O4@SiO2-Py) was found to be an efficient, greener and heterogeneous solid base catalyst for the Knoevenagel condensation of furfural with acetylacetone under optimized reaction conditions. The Knoevenagel condensation product 3-(2-furylmethylene)-2,4-pentanedione (FMP), a jet fuel precursor, was produced in high yield of 85% with 94% conversion of furfural at 100 °C within a period of 4 h. Fe3O4@SiO2-Py catalyst showed excellent stability and recyclability without losing its initial activity.

Sn-Mont was found to be a highly efficient catalyst for self-etherification of 5-(hydroxymethyl)furfural (HMF) to give 5,5′-oxy(bis-methylene)-2-furaldehyde (OBMF). L-B acidity of Sn(OH) 4 species enwrapped into the layers of montmorillonite was responsible for the excellent activity of Sn-Mont catalyst giving almost complete conversion of HMF with 98% selectivity to OBMF. Aprotic non-polar, dichloroethane was most effective solvent due to the facile formation of oxonium ion mediating etherification reaction. The catalyst showed suitable recyclability confirming its appreciable hydrolytic stability in water, and retention of its acidity.