title: Organocatalytic one-pot asymmetric synthesis of 4H,5H-pyrano[2,3-c]pyrazoles.
abstract: An efficient one pot asymmetric synthesis of tetrahydropyrano[2,3-c]pyrazoles has been developed. This class of biologically active heterocycles can be obtained via a secondary amine catalyzed asymmetric Michael/Wittig/oxa-Michael reaction sequence. Remarkably, the title compounds were accessible in good to very good yields and very good to excellent enantioselectivities after a single purification step.
authors.affiliation: Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany. enders@rwth-aachen.de
authors.forename: Dieter
authors.initials: D
authors.lastname: Enders
authors.forename: André
authors.initials: A
authors.lastname: Grossmann
authors.forename: Bianca
authors.initials: B
authors.lastname: Gieraths
authors.forename: Muharrem
authors.initials: M
authors.lastname: Düzdemir
authors.forename: Carina
authors.initials: C
authors.lastname: Merkens
mesh_terms: D002384:Catalysis; D006574:Heterocyclic Compounds, 2-Ring / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D011714:Pyrans / Q000138:chemical synthesis* / Q000737:chemistry; D011720:Pyrazoles / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D006574:Heterocyclic Compounds, 2-Ring; D011714:Pyrans; D011720:Pyrazoles