Synthesis and structure of [ReOSe(2-Se-py)3]: A rhenium(V) complex with selenium(0) as a ligand

Bis(2-pyridyl) diselenide (2-py2Se2, 1) reacts with [ReOCl3(PPh3)2] under the formation of the unusual oxidorhenium(V) complex [ReOSe(2-pySe)3], which was isolated in crystalline form and studied by spectroscopic methods and X-ray diffraction. The oxidorhenium(V) core is bonded to three 2-pyridineselenolato ligands together with a selenium(0) atom. While the rhenium atom is coordinated in a common distorted octahedral coordination sphere, the selenium(0) atom shows a bent T-shaped coordination with Sesingle bondN bonds of 2.13 (1) and 2.28 (1) Å and a Sesingle bondRe bond of 2.387 (1) Å. The oxidation state of the Se(0) atom has been analyzed using calculated atomic charges and the electron localization function (ELF).