Here we report an overview of our synthetic, spectroscopic and structural studies of technetium and rhenium nitrosyl complexes. We review the results from various notes and short papers reported over the past 15 years and discuss their significance in terms of radiopharmaceutical design.
A single new complex is reported, the ReI-NO complex [ReICl2(NO)(py-N(Et)-py)], in which the tridentate ligand di-(2-picolyl)(N-ethyl)amine, (py-N(Et)-py), is coordinated in a meridional manner. This complex was synthesized from the reaction of the ReI-nitrosyl complex ReCl2(NO)(NCMe)3] and the neutral tri-amine ligand py-N(Et)-py in methylene chloride under argon. The bright red species was isolated chromatographically and recrystallized from CH2Cl2/MeOH under diethylether.
A review of literature values for nitrosyl complexes with various ligands bound to the coordination sitetrans- to the nitrosyl group shows only minor variations in the M-N-O bond angle.