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

Rather than achieving bis-deprotonation of the phosphine, reaction of Cp₂Mn (Cp = cyclopentadienyl) with t-BuPH₂ at room temperature yields monodeprotonation of half of the available phosphine in the product (t-BuPH₂)­(η⁵-Cp)­Mn­{μ-(t-BuPH)}₂Mn­(Cp)­(t-BuPH₂) (1). 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 1, 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 1 and an 18-electron count at Mn.