Structures of trans-[PtCl2(PBz3)2], trans-[Ptl2(PBz3)2], trans-[Pt(NCS)2(PBz3)2]·0.5C 6H6 and trans-[Pdl2(PBz3)2]

A series of structures of trans-[MX2(PBz3)2] [M = Pt, X = Cl-; PBz3 = tribenzylphosphine (1), I-, trans-diiodobis(tribenzyl-phosphine)platinum(II) (2), and NCS-, trans-di(thiocyanate)-bis(tribenzylphosphine)platinum(II) (3); M = Pd, X = I-, trans-diiodobis(tribenzylphosphine)palladium(II) (4)] have been characterized by X-ray crystallography. In all compounds each tribenzylphosphine has one benzylcarbon close to the coordination plane. In (1), (2) and (4) those (in-plane) C atoms, from the two different PBz3, exhibit an anti conformation along the P-P axis, while (3) has the gauche conformation. Root mean square (RMS) calculations and half-normal probability plots show that the complexes in (2) and (4) are very similar and the only significant differences between them are the M-P bonds, 2.354 (4) and 2.330 (5) Å, and the M-I bond distances, 2.604(1) and 2.611 (2) Å, for Pd and Pt, respectively. Calculations of the steric demand of the PBz3 ligands based on the Tolman model gave values ranging from 155 to 178° for the effective and 156 to 179° for the Tolman angles, respectively.