Structural characterization of a completely alkyl-substituted Al–Sb Lewis acid–base adduct

Abstract

a b s t r a c tThe Lewis acidebase adduct t-Bu 3 AleSbMe 3 (1), which was synthesized by reaction of equimolar amounts of t-Bu 3 Al and trimethylstibine SbMe 3 , was characterized by multinuclear NMR ( 1 H, 13 C) spectroscopy, elemental analyses as well as by single crystal X-ray diffraction.

Synthesis and solid‐state structures of t‐Bu3Ga–EPh3 Lewis acid–base adducts

“…The 1 H NMR spectra of 1 – 3 each show a singlet for the t ‐Bu groups (1.25 1 , 1.20 2 , 1.27 ppm 3 ), which are shifted to lower field compared to pure t ‐Bu 3 Ga (1.15 ppm). In contrast, the resonances of the Ph groups are slightly shifted to higher field as was previously observed for comparable alane[8e, 12b] and gallane adducts[8d, 12a] of the desired type. In contrast, the 1 H NMR spectrum of a mixture of t ‐Bu 3 Ga and Ph 3 Bi only showed resonances at the same chemical shift of the pure starting reagents (1.15 t ‐Bu; 7.03–7.19 and 7.63–7.68 ppm Ph), even at low temperature (−60 °C), indicating no adduct formation under these conditions.…”

“…In recent years, we reported on the crystal structures of several trialkylalane and ‐gallane adducts of trialkylstibines R 3 Sb and ‐bismuthines R 3 Bi as well as tetraalkyldistibines R 4 Sb 2 and ‐dibismuthines R 4 Bi 2 , respectively. Structural comparison of analogously substituted adducts proved that the relative strength of the donor‐acceptor interaction within the adducts can be qualitatively estimated following a model initially described by Haaland and Frenking, according to which the adduct formation leads to an increase of the M–C bond lengths and a decrease of the C–M–C bond angles compared to the pure MR 3 molecule .…”

Developments in the chemistry of stibine and bismuthine complexes

“…The low melting points of [AlX3(SbR3)] hindered attempts to produce crystals for X-ray analysis, but the structure of [AlI3(Sb i Pr3)] was obtained, and showed the expected pseudo-tetrahedral geometry at aluminium [125]. The structure of [Al t Bu3(SbMe3)], made from Al t Bu3 and SbMe3 in n-pentane, has been determined [129] and the structure of [Al t Bu3(Sb i Bu3)], formed as a by-product of the reaction of Al t Bu3 with Sb2 i Bu4, reported [130].…”

Organoaluminum Complexes with Bonds to s-Block, p-Block, d-Block, and f-Block Metal Centers

“…Stable stibine-alane adducts are available by reaction of trialkylstibines SbR'3 with dialkylchloroalanes R2AlCl [49] and trialkylalanes AlR3 [49][50][51][52][53], respectively. In addition, the first bismuthine-alane [54,55], distibine-alane [53,[55][56][57], and dibismuthine-alane adducts [58] were prepared by reaction of AlR3 with BiR'3, Sb2R'4 and Bi2Et4, respectively, and subsequently structurally characterized.…”