title: Transition-metal-free synthesis of substituted pyridines via ring expansion of 2-allyl-2H-azirines.
abstract: A new strategy to open the 2-allyl-2H-azirines by 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) promotion in metal-free conditions affording 1-azatrienes that in situ electrocyclize to the pyridines in good to excellent yields is reported. The reaction displays a broad substrate scope and good tolerance to a variety of substituents including aryl, alkyl, and heterocyclic groups. In addition, one-pot synthesis of pyridines from oximes via in situ formation of 2H-azirines was achieved.
authors.affiliation: Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637616, Singapore.
authors.forename: Yaojia
authors.initials: Y
authors.lastname: Jiang
authors.forename: Cheol-Min
authors.initials: CM
authors.lastname: Park
authors.forename: Teck-Peng
authors.initials: TP
authors.lastname: Loh
mesh_terms: D001389:Azirines / Q000737:chemistry*; D002384:Catalysis; D015394:Molecular Structure; D011725:Pyridines / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D001389:Azirines; D011725:Pyridines