Linear Oligophosphaalkanes, XXIV. – Syntheses and Structural Characterisation of Cu8 Complexes with Electron‐Deficient Phosphido BridgesReaction of silylphosphanes (Me3Si)RP–CH2–PR(SiMe3) (R = iPr, tBu, 2,4,6,‐Me3C6H2) with four equivalents of copper(1) halides CuX (X = Cl, Br) or a mixture of two equivalents of CuCl and Cul in the presence of pyridine as an auxiliary ligand affords octanuclear copper(1) complexes of composition Cu8X4(RP–CH2–PR)2(Py)n(CH3CN)m (n = 5, m = 0; n = 4, m = 1; X = Cl, Br, I). Multinuclear compounds of this type may also be obtained by deprotonation of the disecondary phosphanes HRP–CH2–PRH (R = iPr, Ph, 2,4,6‐Me3C6H2) with strong organic bases (DBU) in the presence of CuCl and pyridine. The X‐ray structural analysis of Cu8Cl4(iPr–P–CH2–PiPr)2(Py)5 (3a) (space group P21/c) reveals a Cu4(P–C–P)2 skeleton to which four CuCl(Py)n units (n = 1, 2) are coordinated by Cu–Cl and Cu–P bridges. The phosphorus atoms of the electron‐deficient μ3–PRR′ bridges formed thereby show a distorted trigonal bipyramidal coordination with almost planar PCu3 units. Due to the multiple bridging of the Cu(I) ions in 3a the Cu ⃛Cu distances in the Cu8 complex are relatively short (247.1–276.5 pm).