Platinum-Carbon a-Bonds

Cleavage of Platinum-Carbon o-Bonds.—Electrophilic cleavage of metal-carbon bonds may take place either by a direct attack on the bond or by an oxidative addition of the central metal followed by reductive elimination, cf. a recent review. Romeo and co-workers have studied reaction (8), which is first order 

On the other hand, protolysis of the Pt—C bond in rm 5-[PtH(CH2CN)-(PPh3)2] takes place by a two-step oxidative addition-reductive elimination mechanism. Obviously, which mechanism is preferred will probably depend on many factors, such as electronic and steric properties of the complex and its substituents, the nature of the electrophile, and the solvent. 

Miscellaneous.— The reaction between dioxygen platinum(ii) complexes and substituted acetylenes takes place via two discernible steps, according to reaction (9), where R = COaMe and R = cyclohexyl. There is a direct attack by the acetylene on the dioxygen ligand. Formation of u-peroxo- -hydroxo-complexes 

Some mechanistic information about the interaction between platinum complexes and nucleotides has recently appeared see also the reviews and refs. 79, 80, and 98. 

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The most important reaction of platinum(II) alkene complexes is nucleophilic attack at a coordinated carbon atom. The most studied nucleophile in this context is the amine nitrogen. Amines attack coordinated monoalkenes, and if tertiary phosphine or amine ligands are present these stabilize the Zwitterionic platinum-carbon a-bonded complexes that are formed (equation 239) The attack occurs trans to platinum. Substituents adjacent to the... 

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