Design of Manganese Phenol Pi-complexes as Shvo-type Catalysts for Transfer Hydrogenation of Ketones

Article abstract of DOI:10.1002/cctc.201801797

Catalytic hydrogenation is one of the most important reactions both in academic research and industry. We explored ability of the manganese pi-complexes to act as Shvo-type catalysts for transfer hydrogenation of ketones. DFT calculations suggested that the transfer of hydrogen atoms from the hypothetical intermediate [(C₆Me₃H₂OH)Mn(CO)₂H] to acetone has low activation barrier of 10.9 kcal mol^?1. Experimentally a number of ketones with various functional groups (OMe, NH₂, Cl, CF₃, pyridyl) were successfully reduced in isopropanol at 90 °C in the presence of the complex [(C₆Me₃H₂OH)Mn(CO)₃]BF₄ (1 mol %) and ^tBuOK (75 mol %). However, further investigation revealed that the reduction was mainly promoted by base rather than the manganese complex.