A Tin Analogue of Carbenoid: Isolation and Reactivity of a Lithium Bis(imidazolin-2-imino)stannylenoid

The lithium bis(imino)stannylenoid (NIPr)(2)Sn-(Li)Cl (1; NIPr = bis(2,6-diisopropylphenyl)imidazolin-2-imino) was prepared by the reaction of LiNIPr with 0.5 equiv of SnCl2 center dot diox (diox = 1,4-dioxane) and the ambiphilic character of the compound was demonstrated by investigations into its reactivity. Treatment of 1 with I-2 or MeI yielded the oxidative addition products (NIPr)(2)SnI2 and (NIPr)(2)Sn(Me) I, respectively. In contrast, the reaction of 1 with one equivalent of Me3SiCl resulted in the formation of Me3SiNIPr and the chlorostannylene dimer [NIPrSnCl](2). Moreover, the substitution reaction of compound 1 with MeLi led to the formation of the methyl-substituted stannate (NIPr)(2)Sn(Li) Me.