Obviation of hydrogen fluoride in Boc chemistry solid phase peptide synthesis of peptide-αthioesters

Under suitable conditions, trifluoromethanesulfonic acid performs comparably to hydrogen fluoride for the on-resin global deprotection of peptides prepared by Boc chemistry solid phase peptide synthesis (SPPS). Obviation of hydrogen fluoride in Boc chemistry SPPS enables the straightforward synthesis of peptide-athioesters for use in native chemical ligation.