High-Valent Polyoxovanadate-Alkoxide Clusters Synthesis and Their Use in the Dehydrogenation of Alcohols

Polyoxovanadates (POVs) have drawn attention due to their potential in many fields including biological, energy, and catalysis innovations. This project investigates the potential use of POV clusters in the dehydrogenation of alcohols under UV light. The methyl-backed variant ([ⁿBu₄N]₂[V₆O₁₃(TRIOL^Me)₂]) and the nitro-backed variant ([ⁿBu₄N]₂[V₆O₁₃(TRIOL^NO2)₂]) are synthesized from commercially available starting materials like Sodium Orthovanadate (Na₃VO₄), tetrabutylammonium bromide, and the appropriate TRIOL ligand precursor. The alcohols were used to test the clusters’ strength and ability to form the corresponding ketones and aldehydes. Various alcohols, including phenylethanol, isopropanol, pentanol, methanol, and ethanol, have been chosen based on previous research done in this field. Reaction products were characterized using ¹H NMR Spectroscopy and Electronic Absorption Spectroscopy. NMR peaks of the products were then compared to previously published data. Results showed the ability of the clusters to oxidize some alcohols under UV light after a few hours/days like the oxidation of 1-phenylehtanol to acetophenone whereas some alcohols, such as methanol, ethanol, showed slight/ no signs of getting oxidized. The project has room for improvement by choosing a wider range of alcohols and relating the alcohols' structures to their potential to be dehydrogenated. Future work will investigate the potential of creating a catalytic cycle by exposing the reduced clusters to O₂ and converting them to their original oxidized form.