Structure and Bonding of the Manganese(II) Phosphide Complex (<i>t</i>-BuPH₂)(η⁵-Cp)Mn{μ-(<i>t</i>-BuPH)}₂Mn(Cp)(<i>t</i>-BuPH₂)

Rather than achieving bis-deprotonation of the phosphine, reaction of Cp₂Mn (Cp = cyclopentadienyl) with <i>t</i>-BuPH₂ at room temperature yields monodeprotonation of half of the available phosphine in the product (<i>t</i>-BuPH₂)­(η⁵-Cp)­Mn­{μ-(<i>t</i>-BuPH)}₂Mn­(Cp)­(<i>t</i>-BuPH₂) (<b>1</b>). This complex comprises a Mn­(II) phosphide and is a dimer in the solid state, containing a Mn₂P₂ diamond core. Consistent with the observation of a relatively short intermetal distance of 2.8717(4) Å in <b>1</b>, DFT analysis of the full structure points to a singlet ground state stabilized by a direct Mn–Mn single bond. This is in line with the diamagnetic character of <b>1</b> and an 18-electron count at Mn