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One Ligand, One Metal, Seven Oxidation States: Stable Technetium Complexes with the "Kläui Ligand"
Anna C Grunwald1, Clemens Scholtysik1, Adelheid Hagenbach1
1Freie Universität Berlin, Institute of Chemistry and Biochemistry, Fabeckstraße 34/36, D-14195 Berlin, Germany.
Abstract:
A series of technetium complexes with (η5-cyclopentadienyl)tris(dimethyl phosphito-P)cobaltate(III), also known as the "Kläui ligand" {LOMe}-, has been prepared. The products span seven different oxidation states (+1 to +7) of the radioactive transition metal and comprise nitrosyl, halide, oxido and nitrido complexes. All members of this series ([TcI(NO)Cl(PPh3)(LOMe)], [TcII(NO)Cl2(LOMe)], [TcIIICl2(PPh3)(LOMe)], [TcIVCl3(LOMe)], [TcVOCl2(LOMe)], [TcVNCl(PPh3)(LOMe)], [TcVINCl2(LOMe)], and [TcVIIO3(LOMe)] are air- and water-stable compounds, which recommends this class of technetium complexes as potential candidates for nuclear medical imaging procedures.
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