Thiol-Ene Click Reactions - Versatile Tools for the Modification of Unsaturated Amino Acids and Peptides

Terminal gamma,delta-unsaturated amino acids, easily available by Claisen rearrangement or palladium-catalysed allylic alkylation, are excellent substrates for radical thiol additions. These click reactions allow the introduction of highly functionalized side-chains into a given amino acid or peptide. This protocol is suitable for the modification of all kinds of terminal alkenes, such as allyl protecting groups.