Considering that the amide NH groups are neither protected nor deprotonated, reductive samariation in the presence of a carbonyl substrate is a remarkably efficient method for the formation of a C-C bond. This was shown for a series of dipeptides and a tripeptide [Eq. (a)]. For the latter the product was obtained in a good yield of 50 %, despite the presence of three amide protons.
Selective Side Chain Introduction onto Small Peptides Mediated by Samarium Diiodide: A Potential Route to Peptide Libraries
A mild and simple method for the selective introduction of carbinol side chains onto glycine residues in peptides is presented as a potential route for the preparation of peptide libraries. A series of di- and tripeptides, as well as one tetrapeptide, each possessing one glycine residue, were first selectively functionalized at this amino acid unit by a two-step sequence involving bromination with