Synthesis and Characterization of the Monomeric Vicinal Dianion Li₂(THF)₃[ArNC(SiMe₃)₂] and the Aluminum and Lithium Derivatives of the Amido Ligand [ArNCH(SiMe₃)₂]⁻

Reaction of the imine ArNC(SiMe3)2 (1; Ar = 2,6-iPr2C6H3) with LiAlH4 in THF resulted in the formation of the dimeric hydroaluminate [(THF)2LiH3AlL]2 (2; L = [ArNCH(SiMe3)2]−). 2 reacted with CH3I to give the monomeric aluminum dihydride LAlH2(THF) (3), which can be converted to the diiodide LAlI2(THF) (4) upon treatment with 2 equiv of Me3SiI. The quasi two-coordinate lithium amide Li(OEt2)L (8) with an intramolecular CH−Li interaction was obtained by the deprotonation of the corresponding amine LH (5) generated from hydrolysis of 2. Reduction of 1 with lithium in THF resulted in the first structurally characterized monomeric C−N vicinal dianion, Li2(THF)3[ArNC(SiMe3)2] (6), and the monomeric lithium amide Li(THF)2L (7).