Phosphine exchange in trans-chlorobis(methyldiphenylphosphine)[2-(phenylazo)phenyl]platinum(II) promoted by intramolecular nucleophilic attack

Abstract

Temperature variations in ^IH n.m.r. spectra of the title compound, (I), in CDCl₃ or nitrobenzene solutions are interpreted in terms of facile exchange of phosphine. Chemical evidence supporting ready loss of Ph₂MeP from compound (I), together with the failure to observe phosphine exchange in [(Ph₂MeP)₂PtX₂](X = Cl, Br, or I) except when excess of phosphine is present, suggest that an S_Ni mechanism operates in (I) to eliminate Ph₂MeP, which could then participate in S_N2 exchange reactions.