Crystal Structures of Trifluoromethanesulfonato Complexes of Nickel(II) and Palladium(II), [Ni(bpy)₂(CF₃SO₃)₂] and [Pd(triphosphine)(CF₃SO₃)](CF₃SO₃)·C₆H₆, and Characterization of the Coordination Ability of CF₃SO₃⁻

The bis(trifluoromethanesulfonato)nickel(II) complex with two 2,2′-bipyridine (bpy), [Ni(bpy)₂(CF₃SO₃)₂] (1), and the mono(trifluoromethanesulfonato)palladium(II) complex with bis(2-diphenylphosphinoethyl)phenylphosphine (p₃), [Pd(p₃)(CF₃SO₃)](CF₃SO₃)·C₆H₆ (2), were isolated. The crystal structures for 1 and 2 have been determined by an X-ray crystal structure analysis. Complex 1 crystallizes in monoclinic space group Aa with a = 18.55(1), b = 14.48(1), c = 9.941(7) Å, β = 101.98(3)°, and Z = 4. Complex 2 crystallizes in the monoclinic space group P2₁/n with a = 17.211(5), b = 21.175(7), c = 9.962(2) Å, β = 105.66(2)°, and Z = 4. The crystal of 1 contains a distorted octahedral nickel(II) complex with a cis arrangement, and the crystal of 2 contains a distorted square-planar palladium(II) complex. The metal-oxygen bond distances for triflate (CF₃SO₃₋), (2.135(5) and 2.148(4) Å for 1 and 2.126(7) Å for 2), are comparable to those for the other oxygen donors. Three S-O bond distances in the coordinated triflate are close to one another. The stability of the metal-oxygen bond is discussed in terms of the electronic property of triflate.