Room-Temperature Dinitrogen and Carbon Dioxide Activation to Form Nitrogen-Carbon Bonds by Quaternary Cluster Anions: Gold-Assisted Enhancement of Reactivity

Coupling conversion of CO2 and N2 molecules under mild conditions to form useful N-C bond-containing products has attracted significant attention. However, the activation and direct coupling of such very inert molecules are quite challenging. Herein, we determined that this coupling reaction can be realized by AuNbBO- quaternary anions at room temperature. The well-defined AuNbBO- anions can cleave the NN bond in N2 and two C=O bonds in CO2 to form a novel product NCNBO-. To the best of our knowledge, the NCNBO- anion has been experimentally synthesized for the first time by coupling N2 and CO2. Comparative studies with Nb2BO-/N2 and NbBO-/N2 systems further indicate that the presence of a Au atom in AuNbBO- is indispensable for this N2 and CO2 coupling reaction, because the Au atom can decrease the active orbital energies of AuNbBO- anions to facilitate the π-back-donating interaction between AuNbBO- and N2.