Hydroalkylation and hydroacylation of trifluoromethyl olefins by N-centered direct hydrogen atom transfer photocatalysis

Abstract

The selective functionalization of trifluoromethyl olefins, while keeping the essential trifluoroalkyl moiety intact, remains a synthetic challenge. In this study, we report the use of an acridinium amidate as a direct hydrogen atom transfer (d-HAT) photocatalyst for the mild and selective hydroalkylation and hydroacylation of fluorinated olefins. The unique nature of this type of N -centered radical d-HAT system allows an efficient HAT process with a variety of substrates, as well as a single-electron transfer (SET) to obtain the corresponding α-CF 3 carbanion intermediate, while the undesired, typically occurring β-fluoro elimination leading to gem -difluoroalkanes when employing α-trifluoromethyl alkenes as radical acceptors is suppressed by a facilitated last protonation step. This method gives ready access to trifluoromethyl alkanes and can be extended to other fluorinated olefins and to post- and late-stage modifications of pharmaceutically relevant compounds, expanding the toolbox for sustainable and efficient synthesis of highly functionalized fluorinated derivatives under visible light photocatalysis.

The authors' abstract, as published at the source. Cell Reports Physical Science, 2026 · DOI ↗