Solvothermal synthesis and solid-state characterization of metal-metal bonded tetracarboxylatoditechnetium(II,III) polymers

• Published in: Polyhedron Vol. 180; no. C; p. 114418
• Main Authors: Kerlin, William M., Poineau, Frederic, Czerwinski, Kenneth R., Sattelberger, Alfred P., Forster, Paul M.
• Format: Journal Article
• Language: English
• Published: United Kingdom Elsevier Ltd 01.04.2020; Elsevier
• Subjects: Carboxylate-bridged dimers; Hydrothermal synthesis; Metal–metal bonds; Potassium pertechnetate; Technetium; Hydrothermal synthesis; SC-XRD; Metal–metal bonds; FTIR; Potassium pertechnetate; EMAC; SEM; Technetium; XAS; Carboxylate-bridged dimers; LSC; EXAFS
• ISSN: 0277-5387
• DOI: 10.1016/j.poly.2020.114418

The thermal reaction of potassium pertechnetate with glacial acetic acid, under in-situ hydrogen production from the decomposition of sodium borohydride, yields the tetraacetato ditechnetium (II,III) acetate, [Tc2(O2CCH3)4(μ-O2CCH3]n polymer. Substitution of the acetic acid with other carboxylic acids yields related [Tc2(O2CR)4(μ-O2CR]n polymers. [Display omitted] Investigations of solvothermal reactions with pertechnetate, [TcO4]−, have produced four new low-valent Tc extended metal atom chain (EMAC) complexes with multiple metal-metal bonds. The thermal reaction of potassium pertechnetate with glacial acetic acid, under in-situ hydrogen production from the decomposition of sodium borohydride, yields purple elongated crystals determined to be tetraacetato ditechnetium (II,III) acetate (1), [Tc2(O2CCH3)4(μ-O2CCH3]n. Compound 1 was characterized by single crystal X-ray diffraction and its magnetic properties recorded between 10 and 300 K. Single crystal X-ray diffraction analysis of 1 indicates the Tc2+5 tetraacetato unit is linked by the carboxylate oxygens of the bridging acetate, similar to known chloride and bromide linkage polymers of composition [Tc2(μ-O2CCH3)4Cl]n, and [Tc2(μ-O2CCH3)4Br]n. Using the same synthetic method three similar compounds have been synthesized from propionic, benzoic and pivalic acid.