Redox-active dinuclear oxorhenium(V) pyrazolate complexes

Rue, Kelly L.; McLachlan, Jeffrey R.; Cazzaniga, Juliana A.; Chakraborty, Indranil; Dares, Christopher J.; Raptis, Raphael G.

doi:10.1016/j.ica.2020.120126

DOE OSTI · 1852299

Redox-active dinuclear oxorhenium(V) pyrazolate complexes

Rue, Kelly L.·McLachlan, Jeffrey R.·Cazzaniga, Juliana A.·Chakraborty, Indranil·Dares, Christopher J.·Raptis, Raphael G.

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Abstract

Four new structurally similar dinuclear oxorhenium(V) complexes, [{Re(O)X(PPh 3 )} 2 (μ-O)(μ-4-x'-pz) 2 ], where pz = pyrazolate anion, X = X' = Cl (1) and Br (4), X = Cl, X' = Br (2), and X = Br, X' = Cl (3), have been synthesized and characterized. Little variation in spectroscopic features – 1 H NMR, IR, UV–Vis – exists among the four complexes. All complexes possess a bent Re-O-Re core as well as distorted octahedral coordination geometry around the rhenium centers. Finally, a reversible one-electron electrochemical process is observed at approximately 0.84 V vs. Fc + /Fc in all four complexes; however, changing the terminal halide from chloride to bromide slightly destabilizes the oxidized Re(VI) center.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY Chemistry Electrochemistry Pyrazolate ligands Rhenium complexes Spectroelectrochemistry X-ray crystallography

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Rue, Kelly L., McLachlan, Jeffrey R., Cazzaniga, Juliana A., Chakraborty, Indranil, Dares, Christopher J., Raptis, Raphael G.. 2020-11-06. Redox-active dinuclear oxorhenium(V) pyrazolate complexes. https://doi.org/10.1016/j.ica.2020.120126

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