Crystal and Molecular Structure of Binuclear Technetium Carbonyl Chloride Complexes [99TcCl(CO)3(C5H8O2)]2 (C5H8O2 = Acetylacetone) and [99TcCl(CO)4]2

Abstract

The crystal and molecular structures of the complex [⁹⁹TcCl(CO)₃(C₅H₈O₂)]₂ (C₅H₈O₂ = Hacac = acetylacetone) formed in the course of prolonged standing of a [⁹⁹Tc(acac)(CO)₄] solution in ССl₄/CDCl₃ and of its analog containing no organic ligand, [⁹⁹TcCl(CO)₄]₂, were determined. Both complexes contain a [Tc₂(μ-Cl)₂] four-membered ring. The remaining sites in the coordination sphere of the Tc atom are occupied by carbonyl ligands, and in the case of [⁹⁹TcCl(CO)₃(Hacac)]₂, also by the neutral acetylacetone molecule in the enol form. The Hacac molecules in the binuclear complex are in the cis position to the Cl atoms in the octahedral surrounding of the Тс atoms and in the trans position to each other relative to the [Tc₂(μ-Cl)₂] ring. A comparative analysis of the geometries of the complexes and their known analogs was performed.