title: Stereoselective Organocatalyzed Synthesis of α-Fluorinated β-Amino Thioesters and Their Application in Peptide Synthesis.
abstract: α-Fluorinated β-amino thioesters were obtained in high yields and stereoselectivities by organocatalyzed addition reactions of α-fluorinated monothiomalonates (F-MTMs) to N-Cbz- and N-Boc-protected imines. The transformation requires catalyst loadings of only 1 mol % and proceeds under mild reaction conditions. The obtained addition products were readily used for coupling-reagent-free peptide synthesis in solution and on solid phase. The α-fluoro-β-(carb)amido moiety showed distinct conformational preferences, as determined by crystal structure and NMR spectroscopic analysis.
authors.affiliation: ETH Zürich, Laboratory for Organic Chemistry, D-CHAB, Vladimir-Prelog-Weg 1-5/10, 8093, Zürich, Switzerland.
authors.forename: Elena
authors.initials: E
authors.lastname: Cosimi
authors.affiliation: ETH Zürich, Laboratory for Organic Chemistry, D-CHAB, Vladimir-Prelog-Weg 1-5/10, 8093, Zürich, Switzerland.
authors.forename: Oliver D
authors.initials: OD
authors.lastname: Engl
authors.affiliation: ETH Zürich, Laboratory for Organic Chemistry, D-CHAB, Vladimir-Prelog-Weg 1-5/10, 8093, Zürich, Switzerland.
authors.forename: Jakub
authors.initials: J
authors.lastname: Saadi
authors.affiliation: ETH Zürich, Laboratory for Organic Chemistry, D-CHAB, Vladimir-Prelog-Weg 1-5/10, 8093, Zürich, Switzerland.
authors.forename: Marc-Olivier
authors.initials: MO
authors.lastname: Ebert
authors.affiliation: ETH Zürich, Laboratory for Organic Chemistry, D-CHAB, Vladimir-Prelog-Weg 1-5/10, 8093, Zürich, Switzerland. Helma.Wennemers@org.chem.ethz.ch.
authors.forename: Helma
authors.identifier: 0000-0002-3075-5741
authors.initials: H
authors.lastname: Wennemers
mesh_terms: D000577:Amides / Q000737:chemistry*; D002384:Catalysis; D018360:Crystallography, X-Ray; D004952:Esters / Q000138:chemical synthesis* / Q000737:chemistry; D054879:Halogenation; D008958:Models, Molecular; D008968:Molecular Conformation; D010455:Peptides / Q000138:chemical synthesis* / Q000737:chemistry; D011802:Quinidine / Q000031:analogs & derivatives / Q000737:chemistry*; D013237:Stereoisomerism; D013438:Sulfhydryl Compounds / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D000577:Amides; D004952:Esters; D010455:Peptides; D013438:Sulfhydryl Compounds; D011802:Quinidine
keywords: cinchona alkaloids; fluorine; organocatalysis; thioesters; β-amino acids