Gehinderte Ligandenbewegungen in Übergangsmetallkomplexen, XXII [1]. Synthese und Moleküldynamik von OctacarbonyI-μ-(η2:1-ethinyl)-μ-hydrido-dirheniuni(I) / Hindered Ligand Movements in Transition Metal Complexes, XXII [1]. Synthesis and Molecule Dynamics of Octacarbonyl-μ-(η2:1-ethynyl)-μ-hydrido-dirhenium(I)

Abstract

UV-irradiation of decacarbonyl-dirhenium(0) (1) and acetylene in hexane yields a mixture of complexes, which were separated by preparative HPL-chromatography and characterized by elemental analysis, IR, NMR and mass spectroscopy. Main product of the reaction is octa- carbonyl-μ-(η2:1-ethynyl)-μ-hydrido-dirhenium(I) (4). Tricarbonyl-η5-methylcyclopentadienyl- rhenium(I) (2) and tetracarbonyl-2-3:9-η-(8,10-dinorborna-2,5-dien-9-yl)-rhenium(I) (3) are ob­tained in moderate yields. Minor by-products of the reaction are octacarbonyl-μ-hydrido-μ-η2:1- vinyl-dirhenium(I) (5), tridecacarbonyl-μ-η2:1-vinyl-trirhenium (6) and HRe3(CO)14 (7). 4 shows a hindered ligand movement of the η2:1-ethynyl bridge, with ⊿G≠ 250 = 48.2 kJ · mol-1.