202134-23-4Relevant academic research and scientific papers
Crystal structures and vibrational spectra of tetrahalogenoacetylacetonatoosmates(IV), [OsX4(acac)]-, X = Cl, Br, I
Dallmann,Preetz
, p. 1991 - 1996 (1997)
By reaction of the hexahalogenoosmates(IV) with acetylacetone the tetrahalogenoacetylacetonatoosmates(IV) [OsX4(acac)]- (X = Cl, Br, I) are formed, which have been purified by chromatography and precipitated from aqueous solution as tetraphenylphosphonium (Ph4P) or cesium salts. X-ray structure determinations on single crystals have been performed of (Ph4P)[OsCl4(acac)] (1) (triclinic, space group P1, a = 9.9661(6), b = 11.208(2), c = 13.4943(7) A, α = 101.130(9), β = 91.948(6), γ = 96.348(8)°, Ζ = 2), (Ph4P)[OsBr4(acac)] (2) (monoclinic, space group P21/n, a = 9.0251(8), b = 12.423(2), c = 27.834(2) A, β = 94.259(7)°, Ζ = 4) and (Ph4P)[OsI4(acac)] (3) (monoclinic, space group P21/c, a = 18.294(3), b = 10.664(2), c = 18.333(3) A. β = 117.68(2)°, Ζ = 4). Due to the increasing trans influence in the series O ? distances of O?-Cl-X′ axes are lengthened and the OsO? stretching vibrations are shifted to lower frequencies. The Os-X′ bond lenghts are shorter as compared with symmetrically coordinated X-Os-X axes.
