Abstract: | The hydrogenation of carbon dioxide involves the activation of the thermodynamically very stable molecule CO2 and formation of a C−H bond. Herein, we report that HCO2− and CO can be formed in the thermal reaction of CO2 with a diatomic metal hydride species, FeH−. The FeH− anions were produced by laser ablation, and the reaction with CO2 was analyzed by mass spectrometry and quantum‐chemical calculations. Gas‐phase HCO2− was observed directly as a product, and its formation was predicted to proceed by facile hydride transfer. The mechanism of CO2 hydrogenation in this gas‐phase study parallels similar behavior of a condensed‐phase iron catalyst. |