title: Hypervalent Iodine(III)-Mediated Cascade Cyclization of Propargylguanidines and Total Syntheses of Kealiinine B and C.
abstract: An oxidative cascade cyclization of propargylguanidines promoted by phenyliodonium diacetate (PIDA) was developed. The protocol provides an efficient route for the synthesis of the alkaloids kealiinines B and C as well as homologues. The difference in the electronic nature of the acetylene substituent resulted in two ways of the cyclization. A plausible mechanism is proposed based on the experimental results.
authors.affiliation: Laboratory for Organic & Microwave-Assisted Chemistry (LOMAC), University of Leuven (KU Leuven), Celestijnenlaan 200F, 3001, Leuven, Belgium.
authors.forename: Guilong
authors.initials: G
authors.lastname: Tian
authors.affiliation: Laboratory for Organic & Microwave-Assisted Chemistry (LOMAC), University of Leuven (KU Leuven), Celestijnenlaan 200F, 3001, Leuven, Belgium.
authors.forename: Pavel
authors.initials: P
authors.lastname: Fedoseev
authors.affiliation: Laboratory for Organic & Microwave-Assisted Chemistry (LOMAC), University of Leuven (KU Leuven), Celestijnenlaan 200F, 3001, Leuven, Belgium.|Peoples Friendship University of Russia (RUDN University), 6 Miklukho-Maklaya street, Moscow, 117198, Russia.
authors.forename: Erik V
authors.initials: EV
authors.lastname: Van der Eycken
mesh_terms: D000470:Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry; D003500:Cyclization; D006146:Guanidines / Q000737:chemistry*; D007455:Iodine / Q000737:chemistry*; D010084:Oxidation-Reduction
chemical_list: D000470:Alkaloids; D006146:Guanidines; C576859:kealiinine B; D007455:Iodine
keywords: 2-aminoimidazoles; cascade reactions; guanidines; hypervalent iodine; kealiinine alkaloids