title: One-pot access to indolo[2,3-b]quinolines by electrophile-triggered cross-amination/Friedel-Crafts alkylation of indoles with 1-(2-tosylaminophenyl)ketones.
abstract: Activation of C2 and C3 of indoles by molecular iodine (I(2)) and base followed by in situ reaction with 1-(2-tosylaminophenyl)ketones or 2-tosylaminobenzaldehyde can afford highly substituted indolo(2,3-b)quinolines in moderate to excellent yields (up to 99%). The reaction provides a metal-free selective difunctionalization of indoles. The synthetic potential of the protocol has been illustrated by the synthesis of neocryptolepine and its 11-methyl analogue.
authors.affiliation: State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Chinese Academy of Science, Lanzhou 730000, PR China.
authors.forename: Shaukat
authors.initials: S
authors.lastname: Ali
authors.forename: Ying-Xiu
authors.initials: YX
authors.lastname: Li
authors.forename: Saeed
authors.initials: S
authors.lastname: Anwar
authors.forename: Fang
authors.initials: F
authors.lastname: Yang
authors.forename: Zi-Sheng
authors.initials: ZS
authors.lastname: Chen
authors.forename: Yong-Min
authors.initials: YM
authors.lastname: Liang
mesh_terms: D000470:Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry; D000478:Alkylation; D000586:Amination; D001547:Benzaldehydes / Q000138:chemical synthesis* / Q000737:chemistry; D002384:Catalysis; D007211:Indoles / Q000138:chemical synthesis* / Q000737:chemistry; D007659:Ketones / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D011804:Quinolines / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: C572516:2-tosylaminobenzaldehyde; D000470:Alkaloids; D001547:Benzaldehydes; D007211:Indoles; D007659:Ketones; D011804:Quinolines; C414982:neocryptolepine