Tetrylenes chelated by hybrid amido-amino ligand: derivatives of 2-[(N,N-dimethylamino)methyl]aniline

Reaction of 2-(dimethylamino)methyl]aniline with butyllithium, followed by conversion with trimethylsilyl, triphenylsilyl, triphenylgermyl, trimethylstannyl, or tri-n-butylstannyl chloride, gives the corresponding substituted aniline. These compounds were further deprotonated by butyllithium and reacted with germanium, tin, and lead dichlorides, respectively, in both stoichiometric ratios 2:1 and 1:1, providing the target homo- (2-(Me(2)NCH(2))C(6)H(4)(YR(3))N](2)M) and heteroleptic (2-(Me(2)NCH(2))C(6)H(4)(YR(3))N]MCl) germylenes and stannylenes, where M = Ge, Sn, Y = Si, Ge, and R = Me, Ph. Unlike all of these cases, the heteroleptic plumbylene can only be obtained with this reaction when the amide is substituted by a trimethylsilyl moiety. Anilines substituted by trimethyltin or tri-n-butyltin moieties gave transmetalation products after the second deprotonation by butyllithium. The trimethyltin-substituted stannylenes could likewise not be obtained by hexamethyldisilazane elimination of (trimethylstannyl)-2-(dimethylamino)methyl]aniline with 0.5 mol equiv of either bisbis(trimethylsilyl)amido]tin or {bisbis(trimethylsilyl)amido]tin chloride}. Products of these reactions are heterocubanes with compositions {2-(Me(2)NCH(2))C(6)H(4)N]Sn}(4) and 2-(Me(2)NCH(2))C(6)H(4)N](2)(μ(2)-SnMe(2))(2), respectively, and Me(4)Sn or Me(3)SnCl. The structures of trimethylsilyl- and triphenylgermyl-substituted germylenes, stannylenes, and plumbylenes, as well as a number of their precursors, in the crystalline state, were investigated by X-ray diffraction and NMR spectroscopy in solution. Density functional theory methods were used for evaluation of the structures of several compounds.