Binuclear complexes of palladium(II) containing 1,8-diisocyano-p-menthane

Abstract

Well-characterized binuclear isocyano complexes of palladium(II) are obtained with the bridging ligand 1,8-diisocyano-p-menthane (DMB). The ion [Pd2(DMB)4]4+ reacts with X (Cl- or Br-) to give [Pd2(DMB)4X]3+, where the X is positioned between the metal atoms, encapsulated in the complex. Reaction with I- leads to an entirely different product, Pd2(DMB)2I4, which has been characterized by X-ray crystallography: Pd2C24N4H36I4 crystallizes in the monoclinic space group P21/n with a = 11.766 (4) Å, b = 15.123 (8) Å, c = 9.703 (2) Å, β = 93.93 (2)°, and Z = 2. The Pd atoms are square-planar coordinated to two CN groups and two I atoms; the DMB ligands are disordered across a center of symmetry. The coordination planes of the Pd atoms are tilted 35° from the perpendicular to the Pd-Pd vector, and a fifth (axial) site is occupied by an I atom from the other half of the dimer. The Pd⋯Pd distance, 4.582 (1) Å, is such that the ion [Pd2(DMB)4]4+ can accommodate a Br- or Cl- ion between the Pd atoms. © 1984 American Chemical Society.