Formation and X-ray structure of a silver iodide based polymeric complex (Ag5l6)n(Ph3PCH2l)n

Compounds (Ph₃P)₂AgS₂CSR (R = Bu^t, TIPT(2,4,6-triisopropylthiophenolato))], formed by inserting CS₂ into the Ag–S bond in AgSR in the presence of PPh₃, react with CH₂I₂ to give pale yellow crystals of (Ag₅I₆)_n(Ph₃PCH₂I)_n, which consist of the polymeric anion (Ag₅I₆)_n^? and the cation (Ph₃PCH₂)⁺. The polyanion (Ag₅I₆)_n^? is composed of alternate I₅-pentagons and Ag₅-pentagons that are connected by Ag–I bonds along the C axis to form a layered “pagoda” structure, in which there exists an unusual stereochemistry of iodine. Crystal data: monoclinic, space group P2₁/c, a = 15.004(12) Å, b = 27.19(2) Å, c = 7.898 Å, β = 97.18(5)°, V = 3205(4) ų, Z = 4, R = 0.0673 for 2726 observed reflections.