Platinum bonding

FlO. 2. The ethylene-platinum bonding (a), the common representation emphasizing w electron donation (6), the e-bonding molecular orbital (c), the 7r-bonding molecular orbital. 

Cyclic and polymeric phosphazenes will form water-soluble platinum(II) complexes. The compounds contain square planar platinum bonded to the phosphazene via nitrogen.1503-1506... 

While it will undoubtedly require an appreciable amount of effort to precisely and definitively resolve the exact differences between analogous CF3- and CH3-metal bonds, there is no doubt that, in general, perfluoroalkyl-metal bonds are shorter by some 0.05 A than the corresponding alkyl-metal bonds (32-35). In one case, the platinum complexes R2Pt(SP), where R = CF3 or CH3 while SP = o-C2H3Cf)H4Pstructural data have been obtained. The crystallographic results indicate that the carbon platinum bond... 

Both reactions are reversible. Using a dichloroplatinum complex as starting material, formation of the silyl-platinum bond is achieved in the presence of triethylamine ... 

Dewar s landmark contribution [32] did not receive much attention at the time it was published, possibly because the author did not seek to establish the experimental evidence for his model in subsequent publications. He seemed not to be very interested in the field of transition metal chemistry and was probably not aware that his description of the bonding in olefin silver complexes was supported by Raman studies reported a decade previously. In 1941, Harvey Taufen and coworkers had found that the olefin remained largely unchanged in its coordination to Ag+ and that the C=C bond was weakened only slightly by the formation of the olefin silver complex [36]. In contrast to Dewar, Joseph Chatt knew this paper and mentioned the results in a review on the mercuration of olefins, which like Dewar s article was also published in 1951 [37], In his paper, Chatt made a clear distinction between the olefin silver and olefin platinum complexes and argued that, in contrast to the ionized olefin silver(I) salts, in the olefin platinum(II) compounds the metal is present in a covalent state and not as an ion. He also believed that for Ag+ the d-shell was core like and not available in the manner necessary to stabilize the olefin-platinum bond [37]2. 

Binuclear Hydridoplatinum Complexes with Platinum—Platinum Bonds... 

Fig. 3. Schematic molecular orbital representation of the ethylene-platinum bond. Reproduced from J. Chatt and L. A. Duncanson, J. Chem. Soc. 2939 (1953), by permission of the Chemical Society.

Each platinum atom has distorted octahedral coordination geometry if platinum-platinum bonds are included. Each platinum atom is coordinated by a chelating dimethylglyoximato ligand at the in-plane... 

Toluene solutions of the thorium complex, Cp 2Th(PPh2)2 reacts smoothly with Pt(COD)2 in the presence of trimethylphosphine to provide Cp 2Th(/r-PPh2)2Pt(PMe3), a complex with a thorium platinum bond. The latter can be regarded as a formal donor acceptor or dative bond from the filled d shell of Pt into the empty d shell of Th. ... 

Olefin rotation around its coordination axis in such complexes [19, 20], and also a weakening of the ethylene-platinum bond in aqueous solution of Zeise s salt with increasing d concentration [18], have been described. Under the premise of this sequence of reactions, a rate equation quite similar to eq. (13) for constant Pd and C2H4 concentrations could be derived (see [12, pp. 18-19]). This attempt used the following summarized reactions Equation (17) is a summarized reaction including the rate-determining step. 

II. Complexes with Unsupported Platinum-Platinum Bonds. 1... 

COMPLEXES WITH UNSUPPORTED PLATINUM-PLATINUM BONDS... 

Platinum-Platinum Bond Distances in dppm-BRiDGED Platinum(I) Dimers... 

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