Benzylic oxidation of aromatics with cerium(IV) triflate; synthetic scope and mechanistic insight

Abstract

The synthetic utility of cerium(IV) triflate Ce(OTf)₄ as a reagent for benzylic oxidation has been tested for a variety of aromatic compounds. Insight is provided into various factors that govern these oxidations and their progress. It has been shown that the mode of preparation of Ce(OTf)₄ and the % H₂O present in the sample have a marked influence on oxidation ability. A variety of mono- and dialkylbenzenes, haloalkylbenzenes, bicyclic and tricyclic ring systems, and alkoxybenzenes have been surveyed. The method offers an easy to perform one-pot reaction for the room temperature synthesis of aromatic ketones and aldehydes from aromatics and has the potential to find wider application.