Photoinduced reactions of organic compounds with transition metal complexes. III. Formation of a σ-methyl complex of platinum(IV) and a π-ethylene complex of...

Article abstract of DOI:10.1016/0022-328X(84)85062-7

Title full: Photoinduced reactions of organic compounds with transition metal complexes. III. Formation of a σ-methyl complex of platinum(IV) and a π-ethylene complex of platinum(II) in photochemical and thermal reactions of PtCl₆^2- with methyl and ethyl derivatives of tin or germanium. thermal oxidative addition of Me₄Sn to PtCl₄^2- to afford the σ-methyl complex of platinum(IV). The photoinduced reaction of PtCl₆^2- with alkyl derivatives of tin or germanium in acetic acid or acetone is described. The reaction with (CH₃)₄Sn affords the complex Ch₃PtCl₅^2- (I) whereas irradiation of PtCl₆^2- with (CH₃)₂Sn(C₂H₅)₂ leads to the formation of I and [(CH₂CH₂)PtCl₂]₂ (III). Complex III is formed in the reaction with Ge(C₂H₅)₄. The proposed mechanism of electrophilic substitution by the platinum(IV) complex involves electron transfer from the tetraalkylmetal to the platinum(IV) complex and is labelled the S_E1e.t. mechanism. The platinum(II)-ethylene complex III appears to be formed from CH₃CH₂PtCl₅^2- (II) upon light irradiation via β-hydrogen elimination. The thermal reaction of PtCl₆^2- with (CH₃)₄Sn to afford complex I is catalysed by PtCl₄^2-. The thermal reaction of (CH₃)₄Sn with PtCl₄^2- in acetic acid or aqueous acetone affords the σ-methyl complex of platinum(IV).