Synthesis, crystal structures and magnetic properties of two iron (II) tris(pyridyl)phosphine selenides complexes

Abstract

ABSTRACTWe reported the synthesis of tris(pyridyl)phosphine selenide (TppSe) and tris(4-methylpyridin-2-yl)phosphine selenide (MeTppSe), which were prepared by a simple and straightforward one-pot method with red phosphorus in a KOH/DMSO suspension, and treatment of resulted phosphines with selenium in hot toluene. These compounds were characterized by mass spectroscopy, 1H, 13C and 31P NMR spectroscopies and the structure of MeTppSe was characterised by a single-crystal X-ray diffraction. Furthermore, The reactions of selenides with Fe(ClO4)2·6H2O afforded two new iron(II) mononuclear metal complexes [Fe(TppSe)2][ClO4]2·3DMF (1) and [Fe(MeTppSe)2][ClO4]2·2DMF (2). Detailed structural analyses and magnetic susceptibility measurements confirm no spin transition from low-spin to the high-spin state between 2 and 300 K in two iron(II) complexes.