Selenolated Copper Hydride Clusters for Visible-Light Photocatalytic Iodofluoroalkylation of Alkynes.

The photocatalytic iodofluoroalkylation of unsaturated systems is of great interest, with significant potential in the synthesis of fluorinated compounds. Herein, we introduce a selenate-protected Cu18 hydride cluster, [Cu18H9(dppy)6(PhCH2Se)6](PF6)3 (dppy = diphenyl-2-pyridylphosphine, PhCH2Se = benzylselenate), that enables visible light-mediated iodofluoroalkylative difunctionalization of alkynes. Single crystal X-ray structural analysis reveals that the cluster comprises a hydride-embedded hexagonal close-packed Cu18 kernel of the D3d symmetry, coprotected by benzylselenate and dppy ligands. Mechanistic studies suggest the reaction proceeds through a single-electron-transfer process from the photoexcited state [Cu18are similar to those reported in The [Cu18]+ complexes then further oxidize the vinyl radicals to form vinyl cations, completing the redox-neutral catalytic cycle. This work presents an efficient method for synthesizing fluoroalkylated iodoalkenes and offers valuable insights into the design of catalytically active metal clusters for the advancement of organic synthesis.