title: Synthetic development and mechanistic study on Pd(II)-catalyzed cyclization of enediynes to benzo[a]carbazoles.
abstract: Treatment of N,N-dimethyl 2-[2-(2-ethynylphenyl)ethynyl]anilines (1) with 10 mol % of palladium chloride and 2 equiv of cupric chloride in refluxing THF gave benzo[a]carbazoles (6) in good yields. A mechanistic study showed that this reaction must proceed through formation of haloindole (7) followed by a palladium(II)-catalyzed atom transfer cyclization reaction to give the benzo[a]carbazoles.
authors.affiliation: School of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Chin-Chau
authors.initials: CC
authors.lastname: Chen
authors.forename: Lin-Yu
authors.initials: LY
authors.lastname: Chin
authors.forename: Shyh-Chyun
authors.initials: SC
authors.lastname: Yang
authors.forename: Ming-Jung
authors.initials: MJ
authors.lastname: Wu
mesh_terms: D002227:Carbazoles / Q000138:chemical synthesis*; D002384:Catalysis; D003500:Cyclization; D053281:Enediynes / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D010165:Palladium / Q000737:chemistry*
chemical_list: D002227:Carbazoles; D053281:Enediynes; C041514:carbazole; D010165:Palladium