title: Cu(I)-catalyzed regioselective synthesis of pyrazolo[5,1-c]-1,2,4-triazoles.
abstract: Cycloadditions of terminal alkynes to 1,2,4-triazolium N-imides in the presence of base and Cu(I) afford pyrazolo[5,1-c]-1,2,4-triazoles regioselectively. The scope of alkynes, the influence of the electronic nature of the leaving group, and variations in the 1-alkyl substituent were examined. Quantum chemical calculations were employed to explain the distinct reactivity of the propiolates.
authors.affiliation: Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, Florida 32611-7200, USA.
authors.forename: Davit
authors.initials: D
authors.lastname: Jishkariani
authors.forename: C Dennis
authors.initials: CD
authors.lastname: Hall
authors.forename: Alexander A
authors.initials: AA
authors.lastname: Oliferenko
authors.forename: David
authors.initials: D
authors.lastname: Leino
authors.forename: Alan R
authors.initials: AR
authors.lastname: Katritzky
mesh_terms: D002384:Catalysis; D003300:Copper / Q000737:chemistry*; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D011720:Pyrazoles / Q000737:chemistry*; D011789:Quantum Theory; D013237:Stereoisomerism; D014230:Triazoles / Q000737:chemistry*
chemical_list: D009942:Organometallic Compounds; D011720:Pyrazoles; D014230:Triazoles; D003300:Copper