STUDY OF THE EFFECT OF TRIARYLPHOSPHINE LIGANDS ON CHEMICAL HARDNESS OF TRIARYLPHOSPHINEGOLD CATIONS

Exchange reactions with the participation of triarylphosphinegold and phenylmercury 4-fluorothiophenoxides, 4-nitrophenoxides and acetates w ere studied by F-19 NMR spectroscopy. The data on the comparative chem ical hardness of Ar3PAu+ and PhHg(+) cations were obtained based on th e data on the equilibrium constants. The chemical hardness of Ar3PAucations increases as the electron-donating ability of triarylphosphine ligands increases. The effect of these ligands is described by the si gma or sigma(0) constants of substituted phenyl groups and by ionizati on potentials of their electron pairs or the pK(a) values.