Syntheses, Characterizations, and Crystal Structures of Dinitrogen‐Divanadium Complexes Bearing Triamidoamine Ligands

Abstract

We recently reported the syntheses, crystal structures, and protonation reactions of dinitrogen divanadium complexes bearing triamidoamine ligands, ([{V(LR)}2(µ‐N2)] (R = iBu (1), EtBu (2), and iPr2Bn (3)). In this study, we have additionally synthesized two novel dinitrogen‐divanadium complexes with similar derivatives (R = Bn (4) and MeBn (5)), which are characterized spectroscopically and structurally. The X‐ray structures have both revealed a divanadium complex with a bridging N2 ligand. The protonation reactions of the µ‐N2 ligands for 4 and 5 in the presence of M+[C10H8]– (M+ = Na+, K+) and proton source (HOTf or [LutH](OTf)) have given ammonia. Particularly, the NH3 yield from the reaction of 5 with K+[C10H8]– and [LutH](OTf) has been 341 %. Furthermore, mixed valence Na+ adduct of 1, [Na{V(LiBu)}2(µ‐N2)] (6), which is prepared by the reaction of 1 with sodium metal, has been prepared and its crystal structure has also been determined. Compound 6 is electrochemically and spectroscopically characterized, which is also evaluated by DFT calculation method.