75716-24-4Relevant academic research and scientific papers
Aquo chemistry of monoarene complexes of osmium(II) and ruthenium(II)
Hung, Yann,Kung, Wei-Jen,Taube, Henry
, p. 457 - 463 (2008/10/08)
A number of derivatives of η-C6H6OsII (BzOsII) were prepared, exploiting the three positions not preempted by the arene ring and emphasizing ligands which are saturated. The species synthesized include [BzOs(NH3)3]2+, [BzOs(NH3)2Cl]+, and [BzOs(en)Cl]+. It was shown that a 2+ ion, presumably [BzOs(H2O)3]2+, is produced in an acidic solution of BzOsCl2 when Cl- is removed by Ag+. The determination of the acidity of the coordinated water for the aquo species is complicated by the condensation of the hydroxo form. However, [BzOs(en)H2O]2+ prepared from [BzOs(en)Cl]+ by adding Ag+ behaves normally, and the value of pKa was found to be 6.3 at 20°C; for [BzOs(NH3)2H2O]2+ it was found to be 6.4, and for [BzRu(en)H2O]2+ it is 7.9. The quotient governing association of Cl- with [BzOs(en)H2O]2+ was measured as 1.1 × 102. The acidity of the aquo ion and the stability of the chloride complex testify to the electron-withdrawing ability of the arene ring.
