An investigation on the influence of co-ordinated aliphatic amines on the rates of reduction of tetrachlorodiamineplatinum(IV) complexes
Abstract
The reduction reactions of trans- and/or cis-[PtCl4(NRH2)2] by [Fe(η5-C5H5)2], Nal, and [Pt(NEtH2)4][ClO4]2 in the presence of chloride ions have been kinetically investigated in methanol [R = H, Me, Et, Prn, Pri, Bun, Bui, Bus, But, CH2But, CH2Ph, or cyclo-C6H11]. The rate constants for the cis complexes are sensitive to both σ-donor ability and steric hindrance of R, according to relationships of the Taft's type: log kred=a+ρI[–σI(R)]+ρS[–ES(R)]. The rates are increased by lowering the σ-donor ability of R and by increasing its bulkiness; the trans complexes behave similarly.