| Abstract
| - The syntheses of the Sb- and Bi-chiral compounds RR‘SbCl, RR‘BiCl, RR‘SbH, RR‘SbLi·2THF, and RR‘SbNa·TMEDA [R = 2-(Me2NCH2)C6H4, R‘ = CH(Me3Si)2] were achieved in good yields. Structural analyses by 1H NMR in C6D6, C6D5CD3, or (CD3)2SO with a variation of the temperature and by single-crystal X-ray diffraction revealed the intramolecular coordination of the pendant Me2N group on the pnicogen centers in the antimony and bismuth chlorides and on Li or Na in the antimonides. Bismuth inversion is observed in solutions of RR‘BiCl in (CD3)2SO.
- RR‘SbCl (1) and RR‘BiCl (2) [R = 2-(Me2NCH2)C6H4, R‘ = CH(Me3Si)2] form by the reaction of R‘ECl2 (E = Sb,Bi) with RLi. The reaction of 1 with LiAlH4 and metalation with n-BuLi gives RR‘SbH (3) and RR‘SbLi·2THF (4)(THF = tetrahydrofuran). Transmetalation of 4 with sodium tert-butoxide in the presence of TMEDA (TMEDA =tetramethylethylenediamine) leads to RR‘SbNa·TMEDA (5). Structural analyses by 1H NMR in C6D6, C6D5CD3, or(CD3)2SO with a variation of the temperature (1, 2, 4, and 5) and by single-crystal X-ray diffraction (1, 2, 4, and5) revealed the intramolecular coordination of the pendant Me2N group on the pnicogen centers in 1 and 2 and onLi or Na in 4 or 5. The variable-temperature 1H NMR spectra of the hydride 3 in C6D6, C6D5CD3, or (CD3)2SO showthat the pyramidal configuration on antimony is stable up to 100 °C, whereas inversion at the nitrogen is notprevented by internal coordination even at −80 °C. The crystals of 1, 2, 4, and 5 consist of discrete molecules withthe Sb and Bi atoms in an approximately Ψ-trigonal-bipyramidal environment in the cases of 1 and 2 and in apyramidal environment in the cases of 4 and 5. Crystal data for 1: triclinic, space group P1̄, a = 7.243(4) Å, b =10.373(3) Å, c = 15.396(5) Å, α = 79.88°, β = 78.27°, γ = 71.480(10)°, V = 1066.2(7) Å3, Z = 2, R = 0.0614.2: monoclinic, space group P21/n, a = 10.665(2) Å, b = 14.241(2) Å, c = 14.058(2) Å, β = 90.100(10)°, V =2135.1(6) Å3, Z = 4, R = 0.049. 4: monoclinic, space group P21/n, a = 11.552(2) Å, b = 16.518(3) Å, c =15.971(5) Å, β = 96.11(2)°, V = 3030.2(12) Å3, Z = 4, R = 0.0595. 5: monoclinic, space group P21/n, a =9.797(2) Å, b = 24.991(5) Å, c = 14.348(3) Å, β = 94.98(3)°, V = 3499.66(12) Å3, Z = 4, R = 0.0571. Thedissociation of the intramolecular N−pnicogen bond and inversion at the nitrogen occurs when solutions of 1 or 2in C6D6 or C6D5CD3 are heated above 25 or 30° C. 1 and 3−5 are stable with respect to inversion of the configurationat the antimony in C6D6, C6D5CD3, or (CD3)2SO up to 160° C. Bismuth inversion, probably via the edge mechanism,is observed in solutions of 2 in (CD3)2SO at 45 °C but not in C6D5CD3 below 125 °C.
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