Dinitrogen Activation by Dihydrogen and Quaternary Cluster Anions AuNbBO-: Nb- and B-Mediated N2 Activation and Au-Assisted Nitrogen Transfer.

Nitrogen fixation and hydrogenation are important issues in chemistry and industry. Herein, we used mass spectrometry and quantum chemical calculations to identify the quaternary AuNbBO- anions that can efficiently activate N2 and H2 to form imido (or amido) units in the products AuNbBON2H2- under thermal collision conditions. In these reactions, Nb and B atoms work in synergy to dissociate N2 and the Au atom acts as a reducing agent, which facilitates the removal of one activated N atom for the following hydrogenation process; generation of three-centered, two-electron bonds facilitates N2 activation and N transformation. This study shows that the noble metal-assisted early transition metal boronyl cluster is highly reactive to facilitate thermal N-N and H-H bond cleavage, and NH (or NH2) and NBO units, which are important intermediates in N2 hydrogenation reactions, are formed. These findings may provide insight into the design of new catalysts for the synthesis of NH3 from N2 and H2.