Tris(amido)tingold Complexes in Different Oxidation States. First Structural Characterization of a Sn−Au−Au−Sn Linear Chain

The reaction of
[MeSi{Me2SiN(Li)(p-tol)}3(Et2O)2]
with SnCl2 in a 1:1 molar ratio leads the
tris(amido)stannate
[MeSi{Me2SiN(p-tol)}3SnLi(Et2O)]
(1), which further reacts with neutral
[AuCl(PPh3)] and anionic
[PPN][AuCl2],
PPN[AuRCl] (R = C6F5, mes), and
chlorogold(I) complexes yielding
[Au(MeSi{Me2SiN(p-tol)}3Sn)(PPh3)]
(2)
and
[PPN][Au(MeSi{Me2SiN(p-tol)}3Sn)2]
(3) and
[Au(MeSi{Me2SiN(p-tol)}3Sn)(R)]
(R = C6F5, 4; R =
mes,
5), respectively. The reaction of 1 with the
dinuclear gold(II) derivative
[Au2(CH2PPh2CH2)2Cl2]
in a 1:2 ratio
affords
[Au2(CH2PPh2CH2)2(MeSi{Me2SiN(p-tol)}3Sn)2]
(6) . In a similar way but starting from
PPN[Au(C6F5)3Cl]
and reacting with 1 in a 1:1 ratio, the Au(III) complex
[PPN][Au(MeSi{Me2SiN(p-tol)}3Sn)(C6F5)3]
(7) has been
obtained. X-ray crystal structure analyses were performed for
compounds 2 and 6, establishing the Sn−Au
bonds
[d(Au−Sn) = 2.5651(13) and 2.6804(13) Å,
respectively). Compound 6 has a nearly linear
Sn−Au-Au−Sn
array and features the first examples of tin−gold(II)
bonds.