Investigations of Pyridine-2-thiol as a Ligand:  Synthesis and X-ray Structures of the Mixed Mo−Mn Dinuclear Complex CpMoMn(CO)₃(μ-CO)(μ-η²-pyS)(μ-η¹-pyS), the Electron-Deficient Trimolybdenum Cluster Cp₃Mo₃(μ-CO)₂(μ-S)(μ₃-S)(μ-η²-NC₅H₄), and the Mononuclear CpMo(CO)₂(μ-η²-pyS)

The reaction of Mn₂(CO)₆(pyS)₂ (1) with (CpMo(CO)₃)₂ (2) at 110 °C gives the heterodinuclear complex CpMoMn(CO)₃(μ-CO)(μ-η²-pyS))(μ-η¹-pyS) (3), the mononuclear molybdenum complex CpMo(CO)₂(μ-η²-pyS) (4), and the 46-electron trimolybdenum cluster Cp₃Mo₃(μ-CO)₂(μ-S)(μ₃-S)(μ-η²-NC₅H₄) (5). Compound 4 could also be prepared in high yield from the reaction of 2 with pyridine-2-thiol at 110 °C. Compound 3 represents a rare example of a Mo−Mn heterodinuclear complex containing a μ-η²-pyridine-2-thiolato, a μ-η¹-pyridine-2-thiolato, and a cyclopentadienyl ligand. The 46-electron compound 5 represents a unique example of a trimolybdenum compound containing three cyclopentadienyl ligands, an ortho-metalated pyridyl ligand, a capping sulfido, a bridging sulfido, and two semibridging CO ligands. Curiously, although this complex is formally electron deficient, it is unreactive toward two-electron donors. The structures of all the compounds have been unambiguously established by single-crystal X-ray crystallography.