Aryl complexes of platinum

The experimental data reported in the previous sections leave no doubt of the intermediate formation of aryl and alkyl platinum derivatives in the reactions of Pt(ll) and Pt(IV) chloride complexes with arenes and alkanes in aqueous solutions. In the 1980s, it was discovered that the reaction of H PtCCwith arenes in aqueous carboxylic acids produces stable a-aryl complexes of platinum(IV) which can be isolated in crystalline form (see, for example, [43]). 

Heating a solution of HjPtCU and an aromatic compound ArH in the CF3COOH-H2O mixture or in CH3COOH leads to the formation of fairly stable CT-aryl complexes of platinum(IV) in yields up to 95%, which can be isolated in the form of anionic adducts with ammonia after chromatography on sihca gel containing ammonia [43, 44] ... 

Heating a solution of an aromatic compound (for example, benzene or toluene) with Na2PtCl4 in aqueous trifluoroacetic acid affords a a-aryl complex of platinum(II which is much less stable in comparison with a corresponding complex of platinum(IV). However this complex was identified after the oxidation with H2PtClg (at room temperature) to produce the latter derivative [48d] ... 

The collapse of the ion-radical pair may produce the Wheland intermediate which after elimination of the proton is transformed into the o-aryl complex of platinum(IV) ... 

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