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Updated: Sep 13, 2026

Constructing Thioether/Vinyl Sulfide-tethered Helical Peptides Via Photo-induced Thiol-ene/yne Hydrothiolation
Published on: August 1, 2018
Palladium-Catalyzed C-H Thiolation of Phenylalanine-Containing Peptides via In Situ Imine Generation
1Key Laboratory of Catalytic Conversion and Clean Energy in Universities of Shandong Province, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu273165, P. R. China.
Abstract:
We report a palladium-catalyzed C-H thiolation of phenylalanine residues in peptides using diaryl disulfides. Key to this approach is an imine directing group generated in situ from the N-terminal Boc group, which obviates the need for an external auxiliary. The reaction features a broad substrate scope, good functional group tolerance, and scalability, delivering thioether-functionalized peptides in synthetically useful yields. Mechanistic studies suggest an imine-directed C-H activation followed by radical C-S bond formation. This auxiliary-free strategy, which relies on a substrate-derived imine as the directing group, provides a versatile platform for late-stage peptide modifications.
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