Chalcogenolate complexes of ytterbium can be prepared via a number of synthetic approaches. The reaction between Yb metal and PhE-EPh (E = S, Se, T e) in liquid ammonia results in the formation of divalent ytterbium chalcogenolates, which can be isolated as the pyridine coordination complexes (pyridine)4Yb(SC6H5)2 (1) (pyridine)4Yb(SeC6H5)2 (2), and (pyridine)5Yb(TeC6H5)2 (3). Reaction of YbCl3 with 3 equiv of NaTePh results in the reiduction of the metal and the formation of 3 and diphenyl ditelluride. The thiolate 1 and selenolate 2 can be prepared by reducing the corresponding dichalcogenide with a ytterbium/mercury amalgam in THF. All three ytterbium complexes have been characterized by elemental analysis and by NMR, IR, and UV-visible spectroscopy. The visible spectra were found to be concentration dependent. All three complexes have also been characterized by single-crystal X-ray diffraction and shown to be molecular, with trans phenylchacogenolate ligands. Octahedral 1 crystallizes in the triclinic space group PI with a = 8.797(3) Å, b = 9.412(4) Å, c = 9.947(7) Å, α = 87.07(4)°, β = 66.79(4)°, γ = 75.25(3)°, V = 730.9(7) Å3, Z = 1, and = 1.608 g/cm3 (Mo Kα radiation at -115 °C). Octahedral 2 crystallizes in the space group C2/c, with a = 25.67 (6) Å, b = 9.027(4) Å, c = 17.680(3) Å, β = 133.62(2)°, V = 2966(2) Å3, Z = 4, pcalc = 1,795g/cm3 (Mo Kα radiation at -120 °C). The pentagonal bipyramid 3 crystallizes in the space group Pbca, with a = 13.695(9) Å, b = 16.422(8) Å, c = 31.917(7) Å, V = 7178(6) Å3, Z = 8, pcalc = 1.83 g/cm3 (Mo Kα radiation at -120 °C). The metal-chalcogenide bond lengths in all three structures can be predicted with the summation of ionic radii.
All Science Journal Classification (ASJC) codes
- Inorganic Chemistry
- Physical and Theoretical Chemistry