Utility of silver nanoparticles embedded on a covalent organic framework as a highly active catalyst for carboxylative cyclization with CO2: a sustainable route for production of tetronic acids and oxazolidinones

Abstract

The rising amount of carbon dioxide in our atmosphere is a concern regarding our environment. This large amount of CO₂ can be utilized as a C1 source for chemical fixation. Heterogeneous catalysts like covalent organic frameworks (COFs) have been reported to show excellent CO₂ capture ability, which can be used to convert CO₂ to various fine chemicals. Here, we synthesized a silver nanoparticle-incorporated TFPNDA COF. This Ag@TFPNDA-COF was characterized by FTIR, PXRD, SEM, TEM, N₂-adsorption desorption, TGA, and XPS analyses. Then we tested the catalytic activity of the Ag@TFPNDA-COF. This COF shows excellent CO₂ fixation capability in the synthesis of tetronic acids via carboxylative cyclization of propargyl alcohols as well as the formation of oxazolidinones from propargyl alcohols and amines under mild conditions. In addition, the Ag@TFPNDA-COF acted as a heterogeneous catalyst that can be easily separated from the reaction mixture for reuse. Moreover, it showed promising recyclability up to five times in a sustainable route for the production of tetronic acids and oxazolidinones.