CO2 Hydrogenation Catalysts with Deprotonated Picolinamide Ligands

In an effort to design concepts for highly active catalysts for the hydrogenation of CO2 to formate in basic water, we have prepared several catalysts with picolinic acid, picolinamide, and its derivatives, and we investigated their catalytic activity. The CO2 hydrogenation catalyst having a 4-hydroxy-N-methylpicolinamidate ligand exhibited excellent activity even under ambient conditions (0.1 MPa, 25 °C) in basic water, exhibiting a TON of 14700, a TOF of 167 h–1, and producing a 0.64 M formate concentration. Its high catalytic activity originates from strong electron donation by the anionic amide moiety in addition to the phenolic O– functionality.