Theoretical mechanism studies on the competitive CO-induced N–N bond cleavage of N2O with N–O bond cleavage mediated by (η5-C5Me5)Mo[N(iPr)C(Me)N(iPr)](CO)2

Abstract

The reaction mechanism for CO-induced reduction of N₂O mediated by (η⁵-C₅Me₅)Mo[N(ⁱPr)C(Me)N(ⁱPr)](CO)₂ is studied using density functional theory (DFT). Two competitive pathways for the N–O and N–N bond cleavage are investigated in detail. The former generates N₂, CO and a coproduct terminal Mo oxo complex, which is attacked by two CO to recycle the catalyst via oxygen atom transfer (OAT) in a four-step process. The latter contains three steps yielding a nitrosyl, isocyanate complex. The N–N bond cleavage occurs in step 3. The barriers of the key steps are numerically similar in the two paths. The calculated proportion of products is consistent with the experiment. The competition of N–O and N–N bond cleavage is also supported by NBO analysis.