Reaction of Methyllithium with Group 6 Phosphine Dinitrogen Complexes

The reaction of MeLi with several group 6 phosphine end-on dinitrogen complexes of the general formula [ML4(N-2)(2)] (M = Mo or W) is reported. Unlike the isoelectronic complex [CpMn(CO)(2)(N-2)] on which RLi reagents have been reported to add to the N-2 ligand, we show herein that MeLi attacks the metal centre to afford rare anionic trans methyl dinitrogen complexes.