Novel Copper(I) Clusters with 2-(Diphenylphosphanyl)anilide Ligands. Synthesis and Crystal Structures of [Cu6X2(NHR)4] (X = Cl, Br, I; R = C6H4-2-PPh2)

Treatment of copper(I) halides CuX (X = Cl, Br, I) with lithium 2-(diphenylphosphanyl)anilide [Li(HL)] in THF led to the formation of hexanuclear copper(I) complexes [Cu6X2(HL)4] [X = Cl (1), Br (2), I (3)]. In compounds 1–3, the copper atoms are in a distorted octahedral arrangement and the amide ligands adopt a μ3-κP,κ2N bridging mode. Additionally there are two μ2-bridging halide ligands. Each of the [Cu6X2(HL)4] clusters comprises two copper atoms, which are surrounded by two amide nitrogen atoms in an almost linear coordination [Cu–N: 186.2(3)–188.0(3) pm] and four copper atoms, which are connected to an amide N atom, a P atom, and a halogen atom in a distorted trigonal planar fashion [Cu–N: 199.6(3)–202.3(3) pm)].