Computational study of the electrochemical reduction of W(CO)4(2,2'-dipyridylamine)

Quantum mechanical calculations on W(CO)4(4,6-diphenyl-2,2'-bipyridine) (1) and on W(CO)4(2,2'-dipyridylamine) (2) were performed with the aim to shed light on the nature of the electrochemical behaviour previously observed under Ar. DFT confirmed the stability of 1 after 1e reduction, showing agreement between IR-SEC (spectroelectrochemical) data and computed IR frequencies. It has been found that the nature of the electrochemical irreversible behaviour of 2 after 1e reduction is due to a geometry rearrangement in which a single pyridine ring is rotated. In long time scale of the IR-SEC a proton loss accounts for the observed IR spectra. Under CO2 a mechanism of conversion to CO and carbonate ions are herein proposed, and the corresponding transition states individuated.