An enantioselective vinylcyclopropane ring-opening/cycloaddition cascade is described. The active thiyl radical catalysts are generated in situ via UV light-promoted homolysis of cystine-based dimers. Amide-functionalization of the peptide at the 4-proline position is essential for effective asymmetric induction. Stereochemical communication is dependent on steric interactions with this substituent that are enforced by H-bonding to the peptide backbone.
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| http://dx.doi.org/10.1021/acs.orglett.8b00364 | DOI Listing |
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