The coordinatively unsaturated cluster cations [Pt3{M(CO)3}(μ-Ph2PCH2PPh2)3]+ (M = Re, Mn)

Trinuclear and Tetranuclear Platinum−Iridium Cluster Complexes: A Remarkable Metal for Metal Substitution Reaction

“…It should be noted that the formation of mixed-metal clusters by such addition−dissociation sequences is already well-established, − but the present system has unique features. The metal addition step has been observed previously in the formation of a tetrahedral PtRe cluster by reaction of [Pt 3 (μ 3 -CO)(μ-dppm) 3 ] 2+ with [Re(CO) 5 ] - …”

“…Synthesis of Pt 3 Ir Butterfly Clusters. By analogy with the known reaction of [Pt 3 (μ 3 -CO)(μ-dppm) 3 ] 2+ , 1 , with [Re(CO) 5 ] - to give the tetrahedral 54-electron Pt 3 Re cluster [Pt 3 {μ 3 -Re(CO) 3 }(μ-dppm) 3 ] + , it was considered that the reaction of 1 with [Ir(CO) 4 ] - might give a tetrahedral Pt 3 Ir cluster cation. However, the reaction resulted instead in the rapid formation of the dark red 58-electron cluster [Pt 3 {Ir(CO)(μ-CO) 2 }(μ-CO)(μ-dppm) 3 ][PF 6 ], 3 , which has an unusual butterfly structure with the iridium occupying a wingtip position (Scheme ).…”

Models for Platinum−Rhenium Bimetallic Catalysts: Sulfidation of Pt3Re Clusters

“…Characterization of the Sulfido Clusters by Spectroscopic Methods. The IR spectra of the rhenium tricarbonyl complexes generally contained three terminal carbonyl bands with similar values of ν(CO), as in the parent cluster 1 . This is rationalized if the bridging sulfur or oxygen atom addition reactions lead to formal oxidation at platinum, while the oxidation state at rhenium remains at +I throughout.…”

“… a Those distances where a metal−metal bond is proposed are shown in boldface. The accepted range for Pt−Pt-bonded distances is 2.6−2.8 Å; previous values for Pt−Re-bonded distances fall in the range 2.71−2.91 Å, with almost half in the range 2.83−2.87 Å. − b The structure was determined as the BPh 4 salt. …”

“…It has been shown that the coordinatively unsaturated cluster cation [Pt 3 {Re(CO) 3 }(μ-dppm) 3 ] + , ( 1 ; dppm = Ph 2 PCH 2 PPh 2 ) can model some aspects of the bimetallic Pt−Re catalysts. Cluster 1 is remarkably versatile in binding additional ligands, and examples of ligand addition to rhenium only, to platinum only, or at a Pt 2 Re face are known. , Of particular relevance to the present work are oxygen atom additions which occur according to Scheme .…”