Technetium tetrachloride as a precursor for small technetium(IV) complexes

Adelheid Hagenbach; Eda Yegen; Ulrich Abram

doi:10.1021/ic060896u

Technetium tetrachloride as a precursor for small technetium(IV) complexes

Inorg Chem. 2006 Sep 4;45(18):7331-8. doi: 10.1021/ic060896u.

Authors

Adelheid Hagenbach¹, Eda Yegen, Ulrich Abram

Affiliation

¹ Institut für Chemie und Biochemie, Freie Universität Berlin, Fabeckstrasse 34-36, D-14195 Berlin, Germany.

PMID: 16933935
DOI: 10.1021/ic060896u

Abstract

Polymeric technetium tetrachloride reacts with monodentate donor ligands such as THF, acetonitrile, DMSO, thioxane (1-oxa-4-thiacyclohexane), PMe2Ph, PPh3, OPPh3, or OH2 via cleavage of the polymeric network and the formation of [TcCl4(L)2] complexes. The configuration of the products is dependent on the donor atoms such that trans coordination is established with "soft" donor atoms such as sulfur or phosphorus, while cis-[TcCl4(L)2] complexes are formed with the "harder" donors oxygen or nitrogen. The ambivalent thioxane binds to technetium via the sulfur atom. The trans products are air stable and resistant to hydrolysis. The cis complexes, however, undergo stepwise hydrolysis, during which complexes of the composition [Cl3(L)2TcOTc(L)2Cl3] (L = CH3CN, DMSO, or OH2) are formed. They are the first representatives of a new class of technetium(IV) complexes with a bridging oxo ligand. The Tc-O bond lengths in these bridges are between 1.803(1) and 1.823(2) A.