PREPARATION, CHARACTERIZATION AND ORGAN DISTRIBUTION OF THE OXOCHLORO-BIS-(1,10-PHENANTHROLINE)TECHNETIUM(V) CATION

[TcOCl(phen)(2)]Cl-2 was prepared by controlled potential cathodic red uction or dithionite reduction of TcO4- in aqueous alcoholic solution containing 1,10-phenanthroline(phen) monohydrate. The compound was als o obtained by ligand exchange reaction of [TcOCl4](-) with phen-H2O in methanol. The strong IR absorption at 895 cm(-1) was attributed to th e Tc=O stretching vibration. The H-1 NMR spectrum displayed 16 distinc t resonances which were assigned by HH-COSY-experiments to the non-equ ivalent aromatic protons of the two phen ligands. The maximum uptake o f [(TcOCl)-Tc-99m(phen)(2)](2+) of 4.2 % dose/g heart in mice, 1 min p .i., was low, probably reflecting the dipositive charge and the high h ydrophilicity of the complex.