Reactions of the tridentate and tetradentate amine ligands di-(2-picolyl)(N-ethyl)amine and 2,5-bis-(2-pyridylmethyl)-2,5 diazohexane with technetium nitrosyl complexes

The reaction of the Tc(II) nitrosyl complex (Bu4N)[Tc(NO)Cl4] with di-(2-picolyl)(NEt)amine in methanol yields the neutral complex [Tc(NO)Cl(py-N(Et)-py)]. The reaction of the Tc(I) nitrosyl complex [Tc(NO)Cl2(HOMe)(PPh3)2] with this tridentate ligand yields cationic [Tc(NO)Cl(py-N(Et)-py)(PPh3)]Cl. These two complexes have been structurally characterized. The reaction of [Tc(NO)Cl2(HOMe)(PPh3)2] with the tetradentate ligand 1,4-bis-(2-pyridylmethyl)-1,4-diazobutane yields a mixture of products including cationic [Tc(NO)Cl(py-NH-NH-py)]Cl and cationic [Tc(NO)Cl(PPh3)(py-NH-NH∼py)]Cl, with a pyridyl terminus left dangling.

Graphical abstractThe reactions of the Tc(II) complex [TcNOCl4]+ and the Tc(I) complex [TcCl2(NO)(HOMe)(PPh3)2] with tridentate and tetradentate amines ligands are examined and the X-ray crystal structures of the products from these reactions are presented.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Technetium nitrosyl complexes as radiopharmaceutical imaging agents. ► Nitrosyl complexes with polydentate amine ligands. ► X-ray structural analysis of complexes.