218788-15-9Relevant academic research and scientific papers
A mixed-ligand P,S,N-cis-dioxorhenium(V) complex by ligand exchange reactions on trans-monooxo-trichlorobis(triphenylphosphine)rhenium(V): Formation and structural studies
Friebe, Matthias,Jankowsky, Ruediger,Spies, Hartmut,Seichter, Wilhelm,Papadopoulos, Minas,Chiotellis, Efstratios,Johannsen, Bernd
, p. 3711 - 3720 (1998)
In the course of our efforts to synthesize rhenium(V) complexes for potential use in nuclear medicine, tridentate dithiolate ligands were combined with (dialkylamine) ethylene thiols [HS-(CH2)2-NR′2] (R′=alkyl, alkoxy) to form amine group bearing mixed-ligand complexes [ReO(SNS)(S)]. The reaction of HS-CH2-CH2-N-(CH2-CH2-N(C 2H5)2)CH2-CH2-SH (N,N-bis(2-mercaptoethyl)-N′,N′-diethylethylenediamine, 2, as a tris-chelating ligand and 1,4-dioxa-8-azaspiro-N-2-mercaptoethylene - decane, 3, with the neutral Re(V) complex [ReOCl3(PPh3)2], 1, yields, in addition to the expected square-pyramidal 3+1 compound (1,4dioxa - 8 - azaspiro - N - 2 - thiolatoethylene - -decane)N,N - bis(2-mercaptoethyl)(N′,N′ - di - ethyl - ethylenediamine) oxorhenium(V), 4, the new five-coordinated complex [1,4-dioxa-8-azaspiro-N-2-mercaptoethylene-[4,5]-decane(triphenylphosphinato) dioxorhenium(V)], 5. Being the only product in the absence of the tridentate component, 5 has a trigonal-bipyramidal structure, where the coordination sphere is formed by two oxo groups in an uncommon cis-arrangement, S and N from the aminothiolate and by the phosphorus atom from the phosphine group originating from the precursor molecule. The structure was verified by mass, 1H NMR, IR spectroscopy as well as by XRD. In addition, extended x-ray absorption spectroscopy (EXAFS) was applied to both the precursor and the resulting compound 5 to compare the complex structures in the solid and the soluted state. Experiments with 18O labelled water added to the reaction mixture led to 18O in the dioxo core, showing that water is the origin of the additional oxo group.
