Solution and Solid-State Characterization of PbSe Precursors

The addition of lead to diphenyl diselenide in ethylenediamine (en) or pyridine (py) allowed for the observation of the solvento complexes, (en)Pb(SePh)₂ or (py)₂Pb(SePh)₂, respectively. Performing this reaction in dimethyl sulfoxide and subsequent crystallization was found to afford Pb(SePh)₂. Inductively coupled plasma optical emission spectroscopy revealed a 1:2 lead to selenium ratio for all three complexes. Nuclear magnetic resonance spectroscopy confirms that Pb(SePh)₂ is readily solubilized by ethylenediamine, and electrospray ionization mass spectrometry supports the presence of Pb(SePh)₂ moieties in solution. Single-crystal X-ray diffraction analysis of the pyridine adduct, (py)₂Pb(SePh)₂, revealed a seesaw molecular geometry featuring equatorial phenylselenolate ligands. Crystals of Pb(SePh)₂ grown from dimethyl sulfoxide revealed one-dimensional polymeric chains of Pb(SePh)₂. We believe that the lead(II) phenylselenolate complexes form via an oxidative addition reaction.