title: Peptide-Catalyzed Stereoselective Conjugate Addition Reactions of Aldehydes to Maleimide.
abstract: The tripeptide H-dPro-Pro-Asn-NH2 is presented as a catalyst for asymmetric conjugate addition reactions of aldehydes to maleimide. The peptidic catalyst promotes the reaction between various aldehydes and unprotected maleimide with high stereoselectivities and yields. The obtained products were readily derivatized to the corresponding pyrrolidines, lactams, lactones, and peptide-like compounds. (1) H NMR spectroscopic, crystallographic, and computational investigations provided insight into the conformational properties of H-dPro-Pro-Asn-NH2 and revealed the importance of hydrogen bonding between the peptide and maleimide for catalyzing the stereoselective C-C bond formation.
authors.affiliation: Laboratorium für Organische Chemie, ETH Zürich, Vladimir-Prelog-Weg 3, 8093, Zürich, Switzerland.
authors.forename: Claudio E
authors.initials: CE
authors.lastname: Grünenfelder
authors.affiliation: Laboratorium für Organische Chemie, ETH Zürich, Vladimir-Prelog-Weg 3, 8093, Zürich, Switzerland.
authors.forename: Jessica K
authors.initials: JK
authors.lastname: Kisunzu
authors.affiliation: Laboratorium für Organische Chemie, ETH Zürich, Vladimir-Prelog-Weg 3, 8093, Zürich, Switzerland. Helma.Wennemers@org.chem.ethz.ch.
authors.forename: Helma
authors.initials: H
authors.lastname: Wennemers
keywords: addition reactions; asymmetric catalysis; maleimide; organocatalysis; peptides