Synthesis and structures of heterodinuclear organoplatinum(or -palladium)–molybdenum(or -tungsten) complexes: Unexpected structural deformation of heterodinuclear propionylplatinum–tungsten complex having 1,2-bis(diphenylphosphino)ethane ligand

Synthesis of a series of heterodinuclear phenylpalladium–molybdenum(or -tungsten) complexes having a bidentate nitrogen ligand, L2PhPd–MCp(CO)3 (M = Mo, L2 = tmeda (12), bpy (13), phen (14); M = W, L2 = tmeda (15)) by metathetical reactions of PdPhIL2 with Na[MCp(CO)3] and acylplatinum–molybdenum(or -tungsten) complex having a 1,2-bis(diphenylphosphino)ethane ligand, (dppe)(RCO)Pt–MCp(CO)3 (M = Mo, R = Et (16), CH2CMe3 (18); M = W, R = Et (17)) by CO insertion into Pt–C bond in corresponding alkyl analogues (dppe)RPt–MCp(CO)3 (M = Mo, R = Et (6), CH2CMe3, M = W, R = Et (8)) are described. These complexes are characterized by NMR and IR spectroscopies and elemental analyses, and the molecular structures of 12, 13, 17 and 18 are determined by X-ray structure analysis. The geometry at Pt (or Pd) is square planar and the MCp(CO)3 moiety has three-leg piano-stool geometries in these complex expect the propionylplatinum–tungsten complex 17, which shows apparent but unexpected structural deformation at Pt and W, giving twisted square-planar and four-leg piano-stool geometries for platinum and tungsten, respectively.