REARRANGEMENTS IN SQUARE-PLANAR AND SQUARE-PYRAMIDAL COMPLEXES OF PALLADIUM(II) AND PLATINUM(II) CONTAINING THE ENANTIOMERS OF (+/-)-METHYLPHENYL(8-QUINOLYL)ARSINE AND ITS PHOSPHORUS ANALOG

Square-planar complexes containing (+/-)-methylphenyl(8-quinolyl)arsine, As*N, or its phosphorus analogue, P*N, of the type [M(E*N)2](PF6)2 and square-pyramidal complexes of the type [MCl(E*N)2]X (where M = Pd(II) or Pt(II), E = As or P, and X = Cl or PF6) have been prepared in enantiomerically and diastereomerically homogeneous forms and their behavior in solution has been investigated by variable-temperature NMR spectroscopy. The square-planar cations, which have the cis coordination geometry, undergo facile intermolecular ligand redistribution (As > P) for both metals (Pd > Pt); the corresponding square-pyramidal cations show, in addition to the above, even more rapid axial chloro site exchange.