Bio-Inspired Mn(I) Complexes for the Hydrogenation of CO₂ to Formate and Formamide

Developing new, efficient catalysts that contain Earth-abundant metals and simple, robust ligands for CO2 hydrogenation is important to create cost-effective processes of CO2 utilization. Inspired by nature, which utilizes an ortho-OH-substituted pyridine motif in Fe-containing hydrogenases, we developed a Mn complex with a simple N-donor ligand, 6,6′-dihydroxy-2,2′-bipyridine, that acts as an efficient catalyst for CO2 hydrogenation. Turnover numbers of 6250 for hydrogenation of CO2 to formate in the presence of DBU were achieved. Moreover, hydrogenation of CO2 to formamide was achieved in the presence of a secondary amine.