title: “Transition-metal-free” synthesis of carbazoles by photostimulated reactions of 2′-halo[1,1′-biphenyl]-2-amines.
abstract: An efficient and simple protocol for the preparation of a series of 9H-carbazoles by photostimulated SRN1 substitution reactions is presented. Substituted 9H-carbazoles were synthesized in low to excellent yields (up to 96%) through an intramolecular C–N bond formation of 2′-halo[1,1′-biphenyl]-2-amines by the photoinitiated SRN1 mechanism under mild and “transition-metal-free” conditions. The biphenylamines used as substrates were obtained with isolated yields ranging from 21% to 84% by two approaches: (A) the cross-coupling Suzuki–Miyaura reaction and (B) the radical arylation of anilines. Some key aspects of the proposed mechanism were evaluated at the B3LYP/6-311+G* level.
authors.forename: Walter D
authors.initials: WD
authors.lastname: Guerra
authors.forename: Roberto A
authors.initials: RA
authors.lastname: Rossi
authors.forename: Adriana B
authors.initials: AB
authors.lastname: Pierini
authors.forename: Silvia M
authors.initials: SM
authors.lastname: Barolo
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry*; D001713:Biphenyl Compounds / Q000737:chemistry*; D002227:Carbazoles / Q000138:chemical synthesis* / Q000737:chemistry; D002384:Catalysis; D008670:Metals / Q000737:chemistry*; D015394:Molecular Structure; D028561:Transition Elements / Q000737:chemistry*
chemical_list: D000814:Aniline Compounds; D001713:Biphenyl Compounds; D002227:Carbazoles; D008670:Metals; D028561:Transition Elements; C023650:aniline