Computational Design of Cobalt Catalysts for Hydrogenation of Carbon Dioxide and Dehydrogenation of Formic Acid.

A series of cobalt complexes with acylmethylpyridinol and aliphatic PNP pincer ligands are proposed based on the active site structure of [Fe]-hydrogenase. Density functional theory calculations indicate that the total free energy barriers of the hydrogenation of CO2 and dehydrogenation of formic acid catalyzed by these Co complexes are as low as 23.1 kcal/mol in water. The acylmethylpyridinol ligand plays a significant role in the cleavage of H2 by forming a strong Co-Hδ-···Hδ+-O dihydrogen bond in a fashion of frustrated Lewis pairs.