Molecular Structures of HT-[MM′Cl2(μ-Me2Ppy)2] (MM′ = Pd2, PdPt, and Pt2; Me2Ppy = 2-(Dimethylphosphino)pyridine) and HT-[Pd2Cl2(μ-Ph2Ppy)2] (Ph2Ppy = 2-(Diphenylphosphino)pyridine)

Crystal structures of Pd(I) and Pt(I) dinuclear complexes, [MM′Cl2(μ-Me2Ppy)2] (MM′ = Pd2 (1), PdPt (2), and Pt2 (3)) and [Pd2Cl2(μ-Ph2Ppy)2] (4), were determined by the single crystal X-ray diffraction method. Crystal data and final R values are: 1, triclinic, , a = 10.019(2), b = 10.902(2), c = 9.062(1) Å, α = 97.75(2), β = 102.45(2), γ = 82.64(2)°, V = 952.7(3) Å3, Z = 2, and R = 0.047; 2, monoclinic, P21/n, a = 16.532(2), b = 19.205(3), c = 13.260(2) Å, β = 93.86(2)°, V = 4200(1) Å3, Z = 8, and R = 0.043; 3, monoclinic, P21/n, a = 16.515(5), b = 19.095(10), c = 13.233(4) Å, β = 93.15(3)°, V = 4167(3) Å3, Z = 8, and R = 0.047; 4, monoclinic, C2/c, a = 30.505(4), b = 17.896(2), c = 12.983(1) Å, β = 98.52(1)°, V = 7009(1) Å3, Z = 8, and R = 0.041. All of the complexes were found to be the head-to-tail isomer of a side-by-side type dinuclear structure. The metal–metal bond distances of 2.584(1) Å in 1, 2.561(1) Å in 2, 2.573(1) Å in 3, and 2.594(1) Å in 4 are relatively short compared with those in the analogous dinuclear complexes bridged by diphosphine ligands. All of the M–P, M–N, and M–Cl distances in Me2Ppy complexes become shortened in the order of the Pd2 > PdPt > Pt2 complexes.