Co-N doped porous carbon composite derived from the pyrolysis of ZIF-67/lignin as a catalyst for Biginelli and Hantzsch reactions

An effective and sustainable catalytic system based on a cobalt-nitrogen doped porous carbon (Co-N-PC) derived from the pyrolysis of ZIF-67 and lignin is developed. The synthetic process involves mixing ZIF-67 with lignin and then pyrolyzing the mixture to produce Co-N-PC. This composite leverages the great surface area and porosity of the lignin-derived carbon support, along with the catalytic activity of cobalt nanoparticles and the nitrogen doping originating from ZIF-67. The resulting material was analyzed using methods such as FT-IR, XRD, SEM, TEM, EDS, BET and STA. The catalytic effectiveness of the Co-N-PC was scrutinized in the Hantzsch reaction, yielding polyhydroquinolines, and it also efficiently catalyzed the Biginelli reaction to produce dihydropyrimidinones. The catalyst demonstrated a wide range of substrate compatibility and indicated strong tolerance to various functional groups. Additionally, the Co-N-PC displayed remarkable recyclability, maintaining its catalytic performance even after multiple reaction cycles. The improved catalytic activity is due to the synergistic effect of the Co nanoparticles and the nitrogen-doped carbon support, which facilitates substrate adsorption and promotes the reaction. This research provides a sustainable and cost-effective method for producing valuable heterocyclic compounds, utilizing biomass-derived carbon support and an MOF precursor to construct an efficient and reusable catalyst. • Cobalt-nitrogen doped porous carbon (Co-N-PC) was fabricated via pyrolysis of Lignin/ZIF-67 precursor. • Co-N-PC exhibited outstanding catalytic activity in the Biginelli and Hantzsch reactions. • Co-N-PC catalyst could be recovered and reused eight times with minimum changes in its activity.