Relationship between complex formation by 99Tc(IV) and the chemical structure of aliphatic carboxylic acid ligands

Abstract

Chemical reactions of 99TcBr 6 2− and different substituted and unsubstituted aliphatic carboxylic acids have been studied using spectrophotometric, electrophoretic, and chromatographic methods. Unsubstituted di- and tricarboxylic acids were unable to stabilize Tc(IV) against hydrolysis in these reactions. In contrast the hydroxycarboxylic acids were able to replace the bromine ligands of the Tc(IV) complex ion resulting in polymeric anionic complex ions and low molecular weight hydroxycarboxylato technetates(IV), even with a monohydroxy-monocarboxylic acid as ligand.