Synthesis, Characterization, and Crystal Structures of Tris(2-pyridyl)phosphine Sulfide and Selenide

We report the synthesis and structural determinations of tris(2-pyridyl)phosphine sulfide and selenide, which were prepared by the reaction of 2-lithiopyridine with phosphorus trichloride at -100 degrees C, and treatment of resulted (2-pyridyl)phosphine with elemental sulfur or selenium in hot toluene. These compounds were characterized by elemental analysis, melting point determination, mass spectroscopy, IR, 1H, and 31P NMR spectroscopies. Furthermore, the molecular structures of tris(2-pyridyl)phosphine sulfide and selenide were determined by single crystal X-ray analysis and compared with the structures of tris(2-pyridyl)phosphine and tris(2-pyridyl)phosphine oxide. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.