Synthesis, Molecular Structure, and Reactivity of the Tetranuclear Complex [NBu4]2[Pd4(μ-PPh2) 2(μ-Cl)4(C6F5)4]. Molecular Structure of [Pd2(μ-PPh2)(C6F 5)2(bipy)2]ClO4-C6H 14

Article abstract of DOI:10.1021/ic9701930

Anionic tetranuclear complexes with the molecular formula [NBu₄]₂[Pd₄(μ-PPh₂) ₂(μ-X)₄(C₆F₅)₄] [X = Cl (1), Br (2)] were obtained by reaction of [NBu₄]₂[Pd₂(μ-PPh₂) ₂(C₆F₅)₄] and PdCl₂ (or K₂[PdCl₄]) in acetone, followed by reaction with KBr for 2. The reactions of 1 with neutral monodentate (L) or bidentate (L-L) ligands afford the dinuclear derivatives [Pd₂(μ-PPh₂)(μ-Cl)(C₆F₅) ₂L₂] [L = PPh₃ (3), py (4)] or [Pd₂(μ-PPh₂)(C₆F₅) ₂(L-L)₂]ⁿ [n = 1-, L-L = acac (6); n = 1+, L-L = bipy (7) or phen (8)]. The structures of complexes 1 and 7 were determined by single-crystal X-ray diffraction studies. The bis(acetone) solvate of complex 1, [NBu₄]₂[Pd₄(μ-PPh₂) ₂(μ-Cl)₄(C₆F₅) ₄]·2C₃H₆O, crystallizes in the monoclinic system, space group P2₁/c, with a = 11.679(5) A?, b = 16.552(7) A?, c = 23.868(8) A?, β= 101.10(3)°, V = 4527.6(15) A?³, and Z = 2. The central core of the anion has the shape of a rectangle with the four Pd atoms in the corners. The hexane solvate of complex 7, [Pd₂(μ-PPh₂)(C₆F₅) ₂(bipy)₂][ClO₄]·C₆H ₁₄, crystallizes in the monoclinic system, space group P2₁/n, with a = 16.214(3) A?, b = 10.311(2) A?, c = 28.380(6) A?, β= 100.82(3)°, V = 4660(2) A?³, and Z = 4. In both complexes, the long Pd?Pd distances (>3.1 A?) clearly point to the absence of any Pd-Pd interaction.