Abstract
Chiral dimethylindiumaminoalkoxides of general formula Me2InOR+ [OR∗ = (+);(-)-2-piperidyl-methoxy (1), (+);(-)-dimethylamino-2-propoxy (2), (S)-(+)-amino-2-propoxy (3), (S)-α, α-diphenyl-2-pyrrolidinyl-methoxy (4)] have been prepared by reaction of Me3In with the corresponding aminoalcohols HOR∗ and characterized by 1H and 13C nmr spectroscopy and X-ray crystallography. Dimeric molecules of 1–4 are composed of two μ2-O-bridged chelating rings, the latter formed due to N—In donor-acceptor interaction. This geometry is comparable with that of aluminium and gallium analogues previously investigated. In the case of 1 and 4, the formation of the N—In bond proceeds stereospecifically. The absolute structure of 3 and 4 was confirmed by refinement of the Flack parameter.
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1: C2/m; a = 15.999(3) Å, b = 9.803(2) Å, c = 7.410(1) Å, β = 111.04(3)°; Z = 2; density (calc.) = 1.586 Mg/m3; R1 = 0.026 for 944 independent reflections with F 2 > 2σ(F 2).
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2: C2/c; a = 13.184(3) Å, b = 9.987(2) Å, c = 15.851(3) Å, β = 90.66(3)°; Z = 4; density (calc.) = 1.573 Mg/m3; R1 = 0.021 for 1890 independent reflections with F 2 > 2σ(F 2).
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3: P21; a = 8.701(2) Å, b = 11.944(2) Å, c = 8.831(1) Å, β = 113.26(3)°; Z = 2; density (calc.) = 1.725 Mg/m3; R1 = 0.018 for 2873 independent reflections with F 2 > 2σ(F 2).
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4: R3; a = 29.708(4) Å, c = 11.017(2) Å; Z = 9; density (calc.) = 1.265 Mg/m3; R1 = 0.034 for 5890 independent reflections with F 2 > 2σ(F 2).
