title: Transition-Metal-Free Synthesis of Carbazoles and Indoles by an SN Ar-Based "Aromatic Metamorphosis" of Thiaarenes.
abstract: Dibenzothiophene dioxides, which are readily prepared through oxidation of the parent dibenzothiophenes, undergo nucleophilic aromatic substitution with anilines intermolecularly and then intramolecularly to yield the corresponding carbazoles in a single operation. The "aromatic metamorphosis" of dibenzothiophenes into carbazoles does not require any heavy metals. This strategy is also applicable to the synthesis of indoles. Since electron-deficient thiaarene dioxides exhibit interesting reactivity, which is not observed for that the corresponding electron-rich azaarenes, a combination of a thiaarene-dioxide-specific reaction with the SN Ar-based aromatic metamorphosis allows transition-metal-free construction of difficult-to-prepare carbazoles.
authors.affiliation: Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502 (Japan).
authors.forename: M
authors.initials: M
authors.lastname: Bhanuchandra
authors.affiliation: Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502 (Japan).|The Hakubi Center for Advanced Research, Sakyo-ku, Kyoto 606-8502 (Japan).
authors.forename: Kei
authors.initials: K
authors.lastname: Murakami
authors.affiliation: Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502 (Japan).
authors.forename: Dhananjayan
authors.initials: D
authors.lastname: Vasu
authors.affiliation: Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502 (Japan). yori@kuchem.kyoto-u.ac.jp.|ACT-C, JST, Sakyo-ku, Kyoto 606-8502 (Japan). yori@kuchem.kyoto-u.ac.jp.
authors.forename: Hideki
authors.initials: H
authors.lastname: Yorimitsu
authors.affiliation: Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502 (Japan).
authors.forename: Atsuhiro
authors.initials: A
authors.lastname: Osuka
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry*; D002227:Carbazoles / Q000138:chemical synthesis*; D002384:Catalysis; D004583:Electrons; D006571:Heterocyclic Compounds / Q000737:chemistry*; D007211:Indoles / Q000138:chemical synthesis*; D008670:Metals / Q000737:chemistry*; D015394:Molecular Structure; D013876:Thiophenes / Q000737:chemistry*
chemical_list: D000814:Aniline Compounds; D002227:Carbazoles; D006571:Heterocyclic Compounds; D007211:Indoles; D008670:Metals; D013876:Thiophenes; C023650:aniline
keywords: amination; aromatic substitution; fluorescence; sulfur heterocycles; synthetic methods