Platinum complexes with unsaturated amines. Part III. The thermodynamics of formation of complexes (CH2:CH·[CH2]n·LR2R′)+PtCl3–(L = N, P, and As; n= 1 and 2)

Abstract

Stability constants and entropies and enthalpies of formation of platinum(II)–olefin complexes of the type (CH₂:CH·[CH₂]_n·LR₂R′)⁺PtCl₃^–(L = N, P, and As; n= 1 and 2) have been obtained in aqueous solution, by a spectrophotometric method. It is shown that these olefins have affinities for platinum(II) comparable with those of the heavier halide ions. Analysis of the enthalpy and entropy changes indicates that the π-acceptor capacity of the olefin is more important than its σ-donor capacity for the formation of stable platinum–olefin bonds.