Hydrogenation is an important step in the synthesis of many pharmaceuticals, and transfer hydrogenation, where a renewable source for hydrogen is used, is a green and efficient method for this process. It has been shown experimentally that alcohols can be used as a source of hydrogen with iridium (III) catalyst affecting the transfer hydrogenation. The mechanism of this process is unknown. In this research study the mechanism of transfer hydrogenation is investigated computationally, using a model system including carbonyl (CO), amine (NH3), and cyclopentadiene (CP) ligands with methanol as the source of hydrogen. Density Functional Theory (DFT) calculations, using the M06 and APFD functionals, along with an effective core potential on the iridium atom. These functionals are used to determine initial, transition state, and intermediate geometries for proposed mechanisms of transfer hydrogenation including stepwise, concerted, and ion pair mechanisms
