Synthesis and reactivity of novel amino(imino)metallylenes

Novel amino(imino)germylene and stannylene were prepared by conversion of HNIPr [NIPr = bis(2,6-diisopropylphenyl)imidazolin-2-imino] with one equiv of Lappert's reagent (E[N(SiMe₃)₂]₂, E = Ge, Sn). The divalent nature of the iminometallylenes was proved by their reactivity toward Lewis acid [Fe₂(CO)₉] as well as Lewis base [DMAP (para-dimethylaminopyridine)]. Furthermore, azido-substituted stannylene was isolated in its dimeric form [N₃SnNIPr]₂ from the reaction of the iminostannylene with one equiv of trimethylsilyl azide. Notably, the reactions of the iminometallylenes with B(C₆F₅)₃ furnish the cyclic germanium(II) and tin(II) cations, respectively, though methyl-abstraction and ring-closing reaction.