Radical α-Trifluoromethoxylation of Ketones under Batch and Flow Conditions by Means of Organic Photoredox Catalysis
Thibaut Duhail, Tommaso Bortolato, Javier Mateos, Elsa Anselmi, Benson J. Jelier, Antonio Togni, Emmanuel Magnier, Guillaume Dagousset, Luca Dell’Amico
Abstract
-trifluoromethoxy-4-cyano-pyridinium, using the photoredox catalyst 4-CzIPN under 456 nm irradiation, affording the α-trifluoromethoxy ketones in ≤50% isolated yield and complete chemoselectivity. As shown by 29 examples, the reaction is general and proceeds very rapidly under batch (1 h) and flow conditions (2 min). Diverse product manipulations demonstrate the synthetic potential of the disclosed method in accessing elusive trifluoromethoxylated bioactive ingredients.
Topics & Concepts
ChemistryPyridiniumChemoselectivityCatalysisYield (engineering)EnolPhotoredox catalysisKetoneFlow chemistryOrganic chemistryCombinatorial chemistryReaction conditionsPhotochemistryPhotocatalysisMaterials scienceMetallurgyFluorine in Organic ChemistryRadical Photochemical ReactionsCatalytic C–H Functionalization Methods