In the search for the two-electron-reduced intermediate of the tetraaza catalyst [(CoN4H)-N-II(MeCN)](2+) (N4H = 2,12-dimethy1-3,7,11,17-tetraazabicyclo [11.3.1]heptadeca-1(17),2,11,13,15-pentaene) for CO2 reduction and elementary steps that result in the formation of CO product, rapid-scan FT-IR spectroscopy of the visible-light-sensitized catalysis, using Ir(ppy)(3) in wet acetonitrile (CD3CN) solution, led to the observation of two sequential intermediates. The initially formed one-electron-reduced [(CoN4H)-N-I](+)-CO2 adduct was converted by the second electron to a transient [(CoN4H)-N-I](+)-CO2 complex that spontaneously converted CO, to CO in a rate-limiting step on the second time scale in the dark under regeneration of the catalyst (room temperature). The macrocycle IR spectra of the [(CoN4H)-N-I]+-CO2-complex and the preceding one-electron [(CoN4H)-N-I]-CO2 intermediate show close similarity but distinct differences in the carboxylate modes, indicating that the second electron resides mainly on the CO2 ligand. Vibrational assignments are corroborated by C-13 isotopic labeling. The structure and stability of the two-electron-reduced intermediate derived from the time-resolved IR study are in good agreement with recent predictions by DFT electronic structure calculations. This is the first observation of an intermediate of a molecular catalyst for CO2 reduction during the bond-breaking step producing CO. The reaction pathway for the Co tetraaza catalyst uncovered here suggests that the competition between CO2 reduction and proton reduction of a macrocyclic multi electron catalyst is steered toward CO2 activation if the second electron is directly captured by an adduct of CO2 and the one electron -reduced catalyst intermediate.