Electrochemical Deoxygenation of a TiIV–Oxo Complex to Enable Catalytic Reductive Oxygen-Atom Transfer from Organic Molecules
Year: 2026
Type: article
Abstract: Well-defined (TTP)TiII (TTP = 5,10,15,20-tetratolylporphyrin) complexes have been shown to promote stoichiometric deoxygenation of organic molecules, such as sulfoxides and epoxides, forming a stable (TTP)TiIV=O product. Here, we explore strategies to promote catalytic deoxygenation reactivity by regenerating (TTP)TiII through chemical or electrochemical reduction. A survey of Lewis acids revealed the effectiveness of B(OPh)3 in promoting activation and loss of the Ti-oxo group, enabling TiII-mediated reductive oxygen-atom transfer (OAT) of diphenyl sulfoxide. Cyclic voltammetry, coulometry, EPR spectroscopy, and X-ray crystallography have been used to probe and characterize TiIII and TiII species from the electroreductive deoxygenation of the TiIV=O complex. The data implicate a Lewis-acid-coupled electron-transfer deoxygenation pathway for TiIV=O turnover. These fundamental studies are complemented by electrochemical reactions demonstrating catalytic reductive oxygen-atom transfer from sulfoxides, pyridine N-oxides, and epoxides.
DOI: 10.1021/jacs.6c11967
Institution: University of Wisconsin–Madison
Language: English
Subfield: Inorganic Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,500
Awards: G1711593866, G3994591615, Acquisition of a 400 MHz NMR Spectrometer for Chemical Research and Learning, G532464858, G5395662436, MRI: Acquisition of a modern single-crystal X-ray diffractometer with a high dynamic range detector, G8408223924, Upgrade of a Cyber-Enabled Electron Paramagnetic Resonance (EPR) Spectrometer for Research and Education, QExactive (Orbitrap) mass spectrometer, Catalytic Redox Reactions for Pharmaceutical Synthesis
OpenAlex ID: W7207540898