Platinum dimers

Pyrimidinethione complexes, osmium, 37 296 Pyriminethionate, as bridging ligands in platinum dimers, 40 202-205 Pyrochlores, 17 108 Pyrococcus furiosus, 38 344-383 aldehyde ferredoxin oxidoreductase, 38 374-381... 

Pyrophosphites, as bridging ligands in platinum dimers, 40 205-208 Pyrosulfur... 

For [(NH3)8Pt4(l-methyluracil)4Ag]5+ (II), the molecular cation showed crystallographic centrosymmetry with Ag being at the inversion centre. The silver atom thus had square planar coordination with four 0-2 oxygens of 1-methyluracil ligands, two from each platinum dimer. The Ag—O bond distances in this case were 243 and 235 pm, and the Pt—Ag separation was 278.7 pm. 

The complex /rara-PtH(02CH)[PEt3]2 catalyzes the decomposition of formic acid in the presence of sodium formate. A mechanism based on the equilibria described in Scheme 2 has been proposed by Paonessa and Trogler (60). The role of formate ion is to promote catalysis by reaction with the platinum dimer (10) or the solvated complex [frans-PtH(S)L2]+, where S = acetone, to reform the catalytically active monomeric species 11 and 12. 

Formal oxidation numbers are essentially a convention and do not necessarily provide information on the structure and reactivity of a given compound. This is particularly true for a platinum dimer of average oxidation state +3 for which there are difficulties in deciding whether to classify the compound as PtnPtIV or PtinPtm. This subject has been dealt with previously [9] [121] [122] and will be treated only briefly here. 

Among quadruply-bridged platinum dimers, the pyrophosphite (POP) and methylenebisphosphite (PCP)-bridged species, which are the most widely studied [6][84][123-125], exhibit a strong red luminescence at 77 K [126], The substitution of X by Y in Pt2 [X2 species is markedly accelerated by light, and the conversion to Pt2 andX2 is photoinduced [127][128]. The excited-state reactivities of these species could be usefully compared with those of 17-electron monomers and other trapped diradical species. 

A. Platinum Dimers with Sulfate and Phosphate as Bridging Ligands (O—O)... 

F. Platinum Dimers with Other Bridging Ligands... 

J. Structural Characteristics of the Quadruply Bridged Platinum Dimers Spectroscopic Properties and Electronic Structures... 

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