Synthesis and molecular structures of di- and trinuclear molybdenum complexes containing pyridine-2-thiolato (pyS) ligand

Article abstract of DOI:10.1016/0022-328x(95)06037-w

Dinuclear complexes [Mo₂(μ-pyS)₂(CO)₄(PPh₃)₂] (1), [Mo₂(μ-pyS)₂(CO)₅(PPh₃)] (2) and a trace quality of trinuclear complex [Mo₃(μ-pyS)₂(μ₃-pyS)₂(CO)₆] (3) were obtained from the reaction of [Mo(CO)₃(MeCN)₃] with pyridine-2-thione (pySH) and PPh₃ in THF. The crystal structures of 1 · 2C₇H₈ and 3 ·; C₇H₈ have been determined by X-ray diffraction studies. Crystals of 1 · 2C₇H₈ are monoclinic, space group C2/c and Z = 4, with a = 18.797(3), b = 11.143(4), c = 28.157(7) A?, β = 101.23(2)°. The structure was refined to R = 0.050 and Rw = 0.057 for 3146 observed reflections. Crystals of 3 · C₇H₈ are monoclinic, space group P2₁/a and Z = 4, with a = 13.912(2), b = 17.161(2), c = 15.577(3) A?, β = 101.17(1)°. The structure was refined to R = 0.046 and Rw = 0.051 for 4357 observed reflections. The molecule of 1 consists of two Mo(CO)₂(PPh₃) fragments linked by an Mo-Mo bond (2.974(2) A?) and by two doubly-bridging pyS ligands. The compound 3 contains a bent open geometry of three molybdenum atoms (Mo(1)-Mo(2)-Mo(3) angle 122.99(3)°) linked by two Mo-Mo bonds (2.943(1) and 2.950(1) A?) and by two doubly- and two triply-bridging pyS ligands.