Efficient Chemoselective Reduction of N‐Oxides and Sulfoxides Using a Carbon‐Supported Molybdenum‐Dioxo Catalyst and Alcohol

• Published in: ChemCatChem 2019-08, Vol.11 (16), p.4139-4146
• Main Authors: Li, Jiaqi, Liu, Shengsi, Lohr, Tracy L., Marks, Tobin J.
• Format: Article
• Language: English
• Subjects: Alcohol; Aliphatic compounds; Benzyl alcohol; Carbon; Carbon-supported Dioxo-Molybdenum; Catalysis; Catalysts; Chemoselective; Environmentally Friendly; Halogens; Heterogeneous Catalysis; Molybdenum; N-oxide and Sulfoxide Reduction; Recyclability; Reduction; Selectivity; Substrates; Sulfoxides; Toxicity
• ISSN: 1867-3880; 1867-3899
• DOI: 10.1002/cctc.201900436

The chemoselective reduction of a wide range of N‐oxides and sulfoxides with alcohols is achieved using a carbon‐supported dioxo‐molybdenum (Mo@C) catalyst. Of the 10 alcohols screened, benzyl alcohol exhibits the highest reduction efficiency. A variety of N‐oxide and both aromatic and aliphatic sulfoxide substrates bearing halogens as well as additional reducible functionalities are efficiently and chemoselectively reduced with benzyl alcohol. Chemoselective N‐oxide reduction is effected even in the presence of potentially competing sulfoxide moieties. In addition, the Mo@C catalyst is air‐ and moisture‐stable, and is easily separated from the reaction mixture and then re‐subjected to reaction conditions over multiple cycles without significant reactivity or selectivity degradation. The high stability and recyclability of the catalyst, paired with its low toxicity and use of earth‐abundant elements makes it an environmentally friendly catalytic system. Mo@C makes it: The chemoselective reduction of a wide range of N‐oxides and sulfoxides with alcohols using a carbon‐supported dioxo‐molybdenum catalyst is reported. The high stability, earth abundance, and recyclability of the catalyst, paired with its low toxicity represents an environmentally friendly catalytic system.