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.