Abstract
Applications of photoexcited nitroarenes have been underdeveloped in organic synthesis.
Since early reports on the direct excitation of nitroaromatics with harsh UV light,
these synthetically useful reagents have not been tamed for use in modern synthetic
chemistry. We have developed practical synthetic protocols for the anaerobic oxidation
of hydrocarbon substrates using commercially available nitroarenes as photochemically
activated oxidants under visible light. Using this approach, a wide variety of olefins
are anaerobically cleaved to their corresponding carbonyls, and aliphatic C–H bonds
are hydroxylated to give alcohols. The anaerobic reaction conditions enable oxidatively
sensitive functional groups to be tolerated and the employment of visible light makes
this method highly sustainable. Mechanistic studies support that the photoexcited
nitroarene biradical intermediate is responsible for the oxygen atom transfer events.
1 Introduction
2 Alkene Cleavage Promoted by Photoexcited Nitroarenes
3 Photoinduced Nitroarene-Mediated C–H Hydroxylation
4 Conclusions
Key words
photochemistry - nitroarenes - biradical - cleavage of alkenes - olefins - carbonyl
- C–H hydroxylation - anaerobic oxidation