A new class of planar (platinum-mercury) mixed metal clusters containing a [Pt3(CO)3(PR3)3] moiety capped by two HgX units

Platinum−Rhenium−Mercury and Related Cluster Chemistry

“…The mean Pt−Pt distance of 2.621 Å in 6 is only slightly longer than that in 2 (2.6115 Å), indicating that addition of the μ 3 -Hg group has little effect on the Pt−Pt bonding . The Pt−Hg distances of 2.868(2)−2.976(2) Å with a mean value of 2.905 Å in 6 are similar to those of 2.860(2)−2.974(2) Å found in [Pt 3 (μ 3 -Hg)(μ 3 -CO)(μ-dppm) 3 ] + and comparable to those in other clusters containing a Pt 3 (μ 3 -Hg) unit. − The mean Pt−Re distance of 2.780 Å is longer than that of 2.702 Å in 2 . This could be due to the trans influence of the mercury atom or due to steric effects as discussed for 2 [ReO 4 ].…”

“…The dimercury cluster 7 was previously prepared as the [PF 6 ] - salt by reaction of [Pt 3 (μ 3 -CO)(μ 3 -Hg)(μ-dppm) 3 ] 2+ with mercury in the presence of Me 3 NO the closest analogies to 7 are found in the dimercury-capped clusters, with the Pt 3 (μ 3 -Hg) 2 core [Pt 3 (μ 3 -HgX) 2 (μ-CO) 3 L 3 ] (X = Cl, Br, I; L = PCy 3 , PPhCy 2 , PPh i Pr 2 , P i Pr 3 ), of which the cluster with X = Br and L = PPhCy 2 was characterized structurally 1 …”

Cluster Complexes with Bonds Between Transition Elements and Zinc, Cadmium, and Mercury

“…9 4 The closely related neutral clusters [Pt3(jn 2 -CO) 3 (PR 1 R 2 2 ) 3 ] (R 1 = Ph, Cy, Pr 1 ; R 2 = Cy, Pr 1 ) form the ^3-HgX (X = Cl, Br, I) capped clusters ^(u-CC^CPRj^Cm-HgX^] with corequisite formation of mononuclear platinum halides. 95 Like many other halomercurial clusters, these compounds exist as halide-bridged dimers in the solid state. Theoretical models o f all these clusters predict a weak platinum-mercury bond and this is borne out by the lability o f the mercury toward displacement under relatively mild conditions.…”

“…Theoretical models o f all these clusters predict a weak platinum-mercury bond and this is borne out by the lability o f the mercury toward displacement under relatively mild conditions. 95 Most recently, platinum triangles bridged by long-chain diphosphine ligands ([PPh 2 (CH 2 ) n PPh 2 ]; n = 4-6) have been shown to take up either a mercury atom or an Hg 2 , depending on the chain length of the bridging phosphine. Although the exact pathway to these complexes is not well understood, these authors suggest that the cavity size between the bridged Pt 3 triangles is the key factor.…”

THEORETICAL STUDY OF COMPLEXES OF THE TYPE [Pt3(M-L)3(L')3J-X (L=CO,SO2,CNH; L'=PH3,CNH; X=Tl+, Hg0, MPH3+ (M = Cu, Au, Ag))

“…When the [Pt 3 (μ-CO) 3 (PR 3 ) 3 ] cluster reacts with two Hg atoms it forms a sandwich type. It can also react with donors like PR 3 and CO [7]. Thus, the reaction of [Pt 3 (μ 2 -C0) 3 L 3 ] with HgI 2 can be described as a redox reaction, where a part of the platinum(0) cluster is first oxidized to Pt(I) and then to Pt(II), while Hg(II) is reduced to Hg(I).…”