摘要：

The reaction of hexamethyldisilazane with tris[(phosphane)-aurio(I)]oxonium tetrafluoroborates affords the corresponding trinuclear μ3-trimethylsilylimido compounds of the type {[(R3P)Au]3NSiMe3}+ BF4 (1a-f). With (triphenylsilyl)amine and the oxonium reagents the analogous series of Ph3Si derivatives (2a-f) is formed (R = Me, Et, iPr; R3 = Ph2Me; R = Ph, o-Tol). The Et3P-based oxonium salt and (Me3Si)2NH give the dinuclear μ-trimethylsilylamido complex {[(Et3P)Au]2N(SiMe3)2)2}+ BF4 (3) as the main product. The crystal and molecular structures of complexes 2a, 2e, and 3 were determined. The trinuclear cations have a pseudo-tetrahedral structure with small Au-N-Au angles and short Au-Au distances for the SiNAu3 units. The Ph3SiN units in 2a and 2e are capping triangles of gold atoms, while in the cation of 3 the (Me3Si)2N unit is bridging a pair of gold atoms. In the 31P- and 14N-NMR spectra of compounds 1 and 2 (except for 1f and 21) the coupling J(31P,14N) is observed. This coupling is temperature-dependent, owing to changes in the relaxation characteristics in solution at low temperature. The decomposition of compounds 1 and 2 leads to the formation of pentanudear dications {[(R3P)Au]5N}2+ for R = Me, Ph.

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