title: Weak Brønsted acid-thiourea co-catalysis: enantioselective, catalytic protio-Pictet-Spengler reactions.
abstract: The development of one-pot imine formation and asymmetric Pictet-Spengler reactions cocatalyzed by a chiral thiourea and benzoic acid is described. Optically active tetrahydro-beta-carbolines, ubiquitous structural motifs in biologically active natural products, are obtained in high ee directly from tryptamine and aldehyde precursors.
authors.affiliation: Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, USA.
authors.forename: Rebekka S
authors.initials: RS
authors.lastname: Klausen
authors.forename: Eric N
authors.initials: EN
authors.lastname: Jacobsen
mesh_terms: D001547:Benzaldehydes / Q000737:chemistry*; D019817:Benzoic Acid / Q000737:chemistry; D002243:Carbolines / Q000138:chemical synthesis* / Q000737:chemistry; D002384:Catalysis; D003500:Cyclization; D007097:Imines / Q000737:chemistry; D026121:Indole Alkaloids / Q000138:chemical synthesis; D015394:Molecular Structure; D013237:Stereoisomerism; D013890:Thiourea / Q000031:analogs & derivatives* / Q000737:chemistry; D014363:Tryptamines / Q000737:chemistry*
chemical_list: D001547:Benzaldehydes; D002243:Carbolines; D007097:Imines; D026121:Indole Alkaloids; D014363:Tryptamines; D019817:Benzoic Acid; D013890:Thiourea