Benzoselenadiazole-based nanoporous Covalent Organic Polymer (COP) as efficient room temperature heterogeneous catalyst for biodiesel production

Abstract Biodiesel production through esterification of fatty acids by solid heterogeneous catalysts has gained huge importance due to their usefulness as alternative fuel source. Here, we report the synthesis of benzoselenadiazole-based nanoporous covalent organic framework COP-1 via Sonogashira coupling reaction and COP-2 functionalized with SO 3 H group through HSO 3 -Cl treatment with COP-1 . The solid heterogeneous catalyst COP-2 endows the synthesis of biodiesel via esterification of free fatty acids at room temperature at a faster rate. Solid-state 13 C NMR and FT-IR spectroscopic data confirm the synthesis of COP-1 and COP-2 . COP-1 and COP-2 show nanoporous structure with surface area of 471.8 and 158.66 m 2  g −1 and pore size of 11.42 nm and 4.49 nm. The sulfonated nanoporous COP-2 shows excellent catalytic property in the esterification of fatty acids with TON 83.33 and 100% yield.