title: Iodine atom transfer [3 + 2] cycloaddition reaction with electron-rich alkenes using N-tosyliodoaziridine derivatives as novel azahomoallyl radical precursors.
abstract: Treatment of N-tosyliodoaziridine derivatives with Et(3)B efficiently produces various azahomoallyl radical (2-akenylamidyl radical) species which give oxygen-functionalized pyrrolidine derivatives through iodine atom transfer [3 + 2] cycloaddition with electron-rich alkenes such as enol ethers and ketene acetal. The present cycloaddition reaction proceeds regioselectively via C-N bond cleavage of an aziridinylalkyl radical intermediate and addition of the resulting azahomoallyl radicals to the terminal carbon of an alkene. The reaction of alkenes with the cyclohexenylamidyl radical generated from an optically active bicyclic iodoaziridine [(1S,2S,6S)-2-iodo-7-(p-toluenesulfonyl)-7-azabicyclo[4.1.0]heptane, 94% ee] also proceeds to give optically active octahydroindole derivatives (84-93% ee).
authors.affiliation: Tokyo University of Pharmacy and Life Science, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Kitagawa
authors.forename: Shinsaku
authors.initials: S
authors.lastname: Miyaji
authors.forename: Yoichiro
authors.initials: Y
authors.lastname: Yamada
authors.forename: Hiroki
authors.initials: H
authors.lastname: Fujiwara
authors.forename: Takeo
authors.initials: T
authors.lastname: Taguchi