Reactions of the alkyltrihydroaluminate [Li(thf)2{AlH3[C(SiMe3)3]}]2. Crystal structures of [Li(tmen)2][AlH3{C(SiMe3)3}], [AlBr2{C(SiMe3)3}]·thf, [AlI2{C(SiMe3)3}]·thf, [Li(thf)2(µ-NHPh)2{AlH[C(SiMe3)3]}] and [Li(thf)4][Al(NHPh)3{C(SiMe3)3}]

Abstract

The alkyltrihydroaluminate [Li(thf)₂{AlH₃[C(SiMe₃)₃]}]₂ (thf = tetrahydrofuran) reacted (i) with tetramethylethane-1,2-diamine (tmen) to give [Li(tmen)₂][AlH₃{C(SiMe₃)₃}], which crystallises as solvent-separated ion pairs, (ii) with HCl, HBr or Br₂, or I₂ to give, respectively, the alkylaluminium dihalides [AlX₂{C(SiMe₃)₃}]·thf, X = Cl, Br or I, which have been characterised spectroscopically and, when X = Br or I, by X-ray diffraction studies; and (iii) with aniline to give [Li(thf)₂(µ-NHPh)₂{AlH[C(SiMe₃)₃]}] and [Li(thf)₄][Al(NHPh)₃{C(SiMe₃)₃}], which crystallise as anilido-bridged and solvent-separated ion pairs respectively.