Fabrication of nanoscale covalent porous organic polymer: An efficacious catalyst for Knoevenagel condensation

Abstract Porous organic polymer (POP) plays an important role as a catalyst for their unique properties like high porosity, excellent thermal stability and persistence towards various solvents (polar/nonpolar). In this work, a nanoscale spherical POP is fabricated by simple polymerization between triformylphloroglucinol and triaminobenzene at room temperature following Schiff-base condensation. The micro-porosity, morphology, surface charge and functionality of the synthesized POP are thoroughly characterized using the relevant techniques. The POP demonstrates efficient catalysis for Knoevenagel condensation at room temperature with higher % of conversion (~98%). The presence of imine functionality with high negative potential attracts H+ ions to facilitate the catalysis. Available active sites of the material favour to coordinate the loosed water molecule for the formation of the product. Here almost complete product formation (almost 98%) is observed within 2 h at room temperature for Knoevenagel condensation between benzaldehyde and malononitrile. The synthesized catalyst also exhibits efficient reusability with retaining good catalytic stability.