title: Synthesis of 5-azaindolizine derivatives by the palladium-catalyzed intermolecular formal [3+2] cycloaddition of alkylidenecyclopropanes with 1,2-diazines.
abstract: The palladium-catalyzed formal [3+2] cycloaddition reaction of alkylidenecyclopropanes with 1,2-diazines proceeded smoothly to give the corresponding 5-azaindolizine derivatives in good to allowable yields. For example, in the presence of 5 mol % of Pd(PPh(3))(4), the reaction of 1-propylhexylidenecyclopropane with phthalazine or with pyridazine proceeded at 120 degrees C without solvent, and the corresponding 2-(1-butylpentyl)pyrrolo[2,1-a]phthalazine or 6-(1-butylpentyl)pyrrolo[1,2-b]pyridazine was obtained in 61% or 49% yield, respectively.
authors.affiliation: Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan.
authors.forename: Amal I
authors.initials: AI
authors.lastname: Siriwardana
authors.forename: Itaru
authors.initials: I
authors.lastname: Nakamura
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Yamamoto