Reaction of aryl azides with tris(trimethylsilyl)silyllithium: Synthesis of tmeda or thf adducts of [Li{N(Ar)Si(SiMe3)3}] and 1,4-trimethylsilyl migration from oxygen to nitrogen

Reaction of ArN3 (Ar = Ph, p-MeC6H4, 1-naphthyl) with [Li{Si(SiMe3)3}(thf)3] yielded lithium amides [Li{N(Ar)Si(SiMe3)3}L] (L = tmeda or (thf)2). Similar treatment of o-phenylene diazide with 2 equiv. of [Li{Si(SiMe3)3}(thf)3] formed dilithium diamide complex 4. Reaction between o-Me3SiOC6H4N3 and [Li{Si(SiMe3)3}(thf)3] afforded, via 1,4-trimethylsilyl migration from oxygen to nitrogen, [Li{OC6H4{N(SiMe3)Si(SiMe3)3}-2}]2 (5). The structures of complexes 3 and 5 have been determined by single crystal X-ray diffraction techniques.

Graphical abstractAryl azides (ArN3, Ar = Ph, p-MeC6H4 or 1-naphthyl) or o-phenylene diazide react with [Li{Si(SiMe3)3}(thf)3] to give lithium amides [Li{N(Ar)Si(SiMe3)3}L] [L = tmeda or (thf)2] or dilithium diamide [{Li(thf)}2{1,2-(μ-NSi(SiMe3)3)2}C6H4]. Reaction of o-Me3SiOC6H4N3 with [Li{Si(SiMe3)3}(thf)3] affords, via 1,4-trimethylsilyl migration from oxygen to nitrogen [Li{OC6H4{N(SiMe3)Si(SiMe3)3}-2}]2.Figure optionsDownload full-size imageDownload as PowerPoint slide