Selenolated Copper Hydride Clusters for Visible-Light Photocatalytic Iodofluoroalkylation of Alkynes
Qian Xu1, Li Deng1, Er-Yong Liu1
1State Key Laboratory of Bioactive Molecules and Druggability Assessment, Guangdong Basic Research Center of Excellence for Natural Bioactive Molecules and Discovery of Innovative Drugs, College of Chemistry and Materials Science, and Guangdong Provincial Key Laboratory of Supramolecular Coordination Chemistry, Jinan University, Guangzhou 510632, China.
Abstract:
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.
![[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F59739.jpg&w=3840&q=50)
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