PREPARATION AND CHARACTERIZATION OF ETHYLENEDIAMINETRIHALOGENONITROSYLRUTHENIUM(III) COMPLEXES

A mixture of mer- and fac-[RuCl3(en)NO], and mer-[RuX3(en)NO] (X=Br or I) were prepared from the corresponding [RuXsNO]2- (X=Cl, Br, or I) o r hydrous RuX3.NO (X=Cl or Br) and en.2HX (en=ethylene-diamine; X=Cl o r Br). The crystal and molecular structures of mer-[RUX3(en)NO] (X=Cl, Br, or I) were determined by X-ray diffraction. The crystals were iso morphous; triclinic, with space group P1BAR. The final R values were 0 .0411 for [RuCl3(en)NO], 0.0271 for [RuBr3(en)NO], and 0.0535 for [RuI 3(en)NO]. In these complexes, the three halogeno atoms were in the mer idional arrangement and in a position cis to the NO. In all of the mer -complexes, the trans-strengthening effect which is expected to be cau sed by the NO was not observed for the Ru-N(en) bond. The synthesized complexes were also characterized by IR and NMR spectra.