The crystal and molecular stucture of μ-Bis(diphenylarsino)methanehexacarbonyldi-μ-chloro-dirhenium(I)-n-hexane (4/1)

Abstract

The crystal and molecular structure of the n-hexane solvate of μ- bis(diphenylarsino)methane-hexacarbonyldi-μ-chloro-dirhenium(I), Re₂(CO)₆(Ph₂AsCH₂AsPh₂)Cl₂, has been determined by three-dimensional X-ray diffraction methods. The complex crystallizes in the space group Pī with a 15.763(1), b 19.077(1), c 12.233(1) Ǻ and α 88.745(10), β 110.506(5), γ 92.900(6)°. The structure was solved by conventional Patterson and Fourier methods and refined by a block-diagonal least- squares method to R and R_w of 0.045 and 0.054, respectively, for 7061 independent statistically significant reflections collected by counter methods. The crystal consists of discrete molecules of the complex and n-hexane held together by van der Waals forces. There are two molecules of the dirhenium complex in the crystallographic asymmetric unit with the n-hexane molecule situated about a site of symmetry ī. The binuclear rhenium complex contains bridging halogen atoms and a bridging diarsine ligand. Three carbonyl ligands are also bonded to each rhenium atom, giving the metal atoms approximately octahedral environments. The average Re-As, Re-Cl, and Re-C bond lengths are 2.58, 2.52, and 1.89 Ǻ respectively.