title: Investigation of Lewis acid-catalyzed asymmetric aza-Diels-Alder reactions of 2H-azirines.
abstract: Asymmetric Diels-Alder reactions with 2H-azirines as dienophiles have been studied. Diastereoselective reactions with an enantiopure azirine 1b, bearing a chiral auxiliary, gave substituted bi- and tricyclic tetrahydropyridines in high yield and stereoselectivity, under the influence of a Lewis acid. The novel enantioselective [4+2] cycloaddition reaction of 3-benzyl-2H-azirine carboxylate with cyclopentadiene was investigated with various chiral Lewis acid complexes and provided the corresponding tetrahydropyridines in moderate to low yield and enantioselectivity.
authors.affiliation: Department of Chemistry, Organic Chemistry, Royal Institute of Technology (KTH), SE-100 44 Stockholm, Sweden.
authors.forename: Asa Sjöholm
authors.initials: AS
authors.lastname: Timén
authors.forename: Peter
authors.initials: P
authors.lastname: Somfai
mesh_terms: D001389:Azirines / Q000737:chemistry*; D002384:Catalysis; D003517:Cyclopentanes / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D011725:Pyridines / Q000138:chemical synthesis; D013237:Stereoisomerism
chemical_list: D001389:Azirines; D003517:Cyclopentanes; D011725:Pyridines