Investigations of Pyridine-2-thiol as a Ligand:  Synthesis and X-ray Structures of the Mixed Mo−Mn Dinuclear Complex CpMoMn(CO)<sub>3</sub>(μ-CO)(μ-η<sup>2</sup>-pyS)(μ-η<sup>1</sup>-pyS), the Electron-Deficient Trimolybdenum Cluster Cp<sub>3</sub>Mo<sub>3</sub>(μ-CO)<sub>2</sub>(μ-S)(μ<sub>3</sub>-S)(μ-η<sup>2</sup>-NC<sub>5</sub>H<sub>4</sub>), and the Mononuclear CpMo(CO)<sub>2</sub>(μ-η<sup>2</sup>-pyS)

The reaction of Mn<sub>2</sub>(CO)<sub>6</sub>(pyS)<sub>2</sub> (<b>1</b>) with (CpMo(CO)<sub>3</sub>)<sub>2</sub> (<b>2</b>) at 110 °C gives the heterodinuclear complex CpMoMn(CO)<sub>3</sub>(μ-CO)(μ-η<sup>2</sup>-pyS))(μ-η<sup>1</sup>-pyS) (<b>3</b>), the mononuclear molybdenum complex CpMo(CO)<sub>2</sub>(μ-η<sup>2</sup>-pyS) (<b>4</b>), and the 46-electron trimolybdenum cluster Cp<sub>3</sub>Mo<sub>3</sub>(μ-CO)<sub>2</sub>(μ-S)(μ<sub>3</sub>-S)(μ-η<sup>2</sup>-NC<sub>5</sub>H<sub>4</sub>) (<b>5</b>). Compound <b>4 </b>could also be prepared in high yield from the reaction of <b>2</b> with pyridine-2-thiol at 110 °C. Compound <b>3</b> represents a rare example of a Mo−Mn heterodinuclear complex containing a μ-η<sup>2</sup>-pyridine-2-thiolato, a μ-η<sup>1</sup>-pyridine-2-thiolato, and a cyclopentadienyl ligand. The 46-electron compound <b>5</b> 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.