The role of the proton in technetium reduction and complexation

In order to understand the reduction and complexation processes of Tc, a study was made of the role of the proton, in the presence and absence of a ligand and co-ordinating group, in these two processes. Solvents used were acetonitrile, DMF, DMSO, tetramethylurea, and ligands were oxine, aminophenol, catechol, resorcinol and quinoline-carboxylic acids. External proton sources were ammonium ions and phenols. Results support the conclusion that the reduction of Tc below (IV) required a reducing agent, proton source and appropriate coordinating group. (U.K.)