Photochemical Insights on Acyl Azolium Salts Enable the Design of a Tandem Hydrogen Atom Transfer/Halogen Atom Transfer Acylation of Alkyl Bromides and Chlorides.

ABSTRACT: Acyl azolium salts have been recently described as good HAT mediators in their excited state-similarly to diaryl ketones-and good acylating reagents, with the beneficial property of enabling incorporation of the acyl residue into the final molecule. Nevertheless, despite significant synthetic efforts in the field, knowledge and understanding of the key reactive intermediates─especially through spectroscopic investigations─remain elusive. Herein, we present a photochemical study of the reactivity of acyl azolium salts that comprises the detection and characterization of the triplet excited state and the decisive ketyl radical intermediate. Moreover, this mechanistic insight allowed us the development of an alternative method based on a silane-mediated tandem HAT/XAT activation strategy that

SUBMITTER: MacLean I 

PROVIDER: S-EPMC12395483 | biostudies-literature | 2025 Aug

REPOSITORIES: biostudies-literature