The Construction of P−O/P−N Ligands on Platinum and Palladium

A variety of diphenyldiphosphinites have been prepared in a very stable form as Pt II or Pd II complexes by adding diols to a solution containing cis ‐[MCl 2 (PPh 2 Cl) 2 ] (M = Pt or Pd) preformed in situ from cis ‐[MCl 2 (1,5‐COD)] (M = Pt; M = Pd) and PPh 2 Cl. This synthetic pathway can be used for diphosphinites derived from aliphatic 1,2 and 1,3 diols and also from the aromatic catechol. Besides the P−O bond, it is also shown here that the P−N bond can also be formed via nucleophilic attack of an amine group on coordinated PPh 2 Cl in the presence of a base resulting in some AMPP and BAMP complexes of Pt II and Pd II . The X‐ray crystal structures of the [ cis ‐1,2‐cyclohexanediyl bis(diphenylphosphinite)]platinum dichloride, of the AMPP palladium complex from (1 R, 2 S )‐(−)‐norephedrine and of the BAMP palladium complex [ P , P ′‐diphenyl‐1,2‐cyclohexanediylbis(imino)bisphosphane]palladium dichloride have been determined. The chemical and optical stabilities of many complexes in solution have been monitored by 31 P NMR spectroscopy. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)