The chemistry of trichloro[tris(trimethylsilyl)methyl] and trichloro[tris(dimethylphenylsilyl)methyl] complexes of gallium, indium, and thallium. Crystal and molecular structures of [Li(thf)2(µ-Cl)2GaCl-{C(SiMe2Ph)3}]·thf, [Li(thf)3(µ-Cl)InCl2{C(SiMe3)3}], and [{(Me3Si)3C}In(µ-Cl)2{µ-Fe(CO)4}ln{C(SiMe3)3}](thf = tetrahydrofuran)

Abstract

Tris(trimethylsilyl)methyl-lithium and tris(dimethylphenylsilyl)methyl-lithium react with gallium(III)indium(III), or thallium(III) chlorides to give alkylmetalates Li(thf)_nMCl₃R [M = Ga, R = C(SiMe₃)₃(1) or C(SiMe₂Ph)₃(2), n= 2; M = In, R = C(SiMe₃)₃(4) or C(SiMe₂Ph)₃, (5), n= 3; M = Tl, R = C(SiMe₃)₃(11), n= 1]. X-Ray studies show that the gallium compound (2) has the structure [Li(thf)₂(µ-Cl)₂GaCl{C(SiMe₂Ph)₃}]·thf with two bridging chlorides between Ga and Li but that there is only one bridging chloride in the indium compound [Li(thf)₃(µ-Cl)InCl₂{C(SiMe₃)₃}](4). The ‘alkyltrichlorometalates’ are reduced by lithium aluminium hydride to ‘alkyltrihydridometalates’. The indium compound can be converted into the chloride hydroxide InCl{C(SiMe₃)₃}(OH) and the oxide hydroxide [{In[C(SiMe₃)₃]}₄(µ₄-O)(µ-OH)₆]. The trichloroindate (4) reacts with Na₂[Fe(CO)₄] to give the yellow complex [{(Me₃Si)₃C}In(µ-Cl)₂{µ-Fe(CO)₄}In{C(SiMe₃)₃}], in which the In ⋯ In distance is 304.8(1) pm. The trichlorothallate (11) decomposes on heating to give first TICl₂{C(SiMe₃)₃} and then {C(SiMe₃)₃}Cl; it reacts with lithium aluminium hydride to give a trihydrido[tris(trimethylsilyl)methyl]aluminate.