title: Synthesis of N-alkyl-3-sulfonylindoles and N-alkyl-3-sulfanylindoles by cascade annulation of 2-alkynyl-N,N-dialkylanilines.
abstract: An efficient and metal-free approach to N-alkyl-3-sulfonylindoles and N-alkyl-3-sulfanylindoles from 2-alkynyl-N,N-dialkylanilines has been developed. In the presence of iodine and tert-butylhydroperoxide (TBHP), a variety of 2-alkynyl-N,N-dialkylanilines underwent a cascade radical annulation to yield 3-arylsulfonylindoles. In contrast, 3-arylsulfanylindoles were conveniently prepared by iodine mediated electrophilic annulation reactions. The present protocol uses the economical and environmentally friendly I2-TBHP or I2system, and potentially bioactive N-alkyl-3-sulfonylindoles and N-alkyl-3-sulfanylindoles with various functional groups were successfully synthesized in moderate to good yields.
authors.affiliation: Department of Chemistry and Center of Excellence for Innovation in Chemistry (PERCH-CIC), Faculty of Science, Mahidol University, Rama 6 Road, Bangkok 10400, Thailand. chutima.kon@mahidol.ac.th.
authors.forename: Jatuporn
authors.initials: J
authors.lastname: Meesin
authors.forename: Manat
authors.initials: M
authors.lastname: Pohmakotr
authors.forename: Vichai
authors.initials: V
authors.lastname: Reutrakul
authors.forename: Darunee
authors.initials: D
authors.lastname: Soorukram
authors.forename: Pawaret
authors.initials: P
authors.lastname: Leowanawat
authors.forename: Chutima
authors.initials: C
authors.lastname: Kuhakarn
mesh_terms: D000480:Alkynes / Q000737:chemistry*; D000814:Aniline Compounds / Q000737:chemistry*; D060326:Chemistry Techniques, Synthetic; D007211:Indoles / Q000138:chemical synthesis* / Q000737:chemistry*; D020122:tert-Butylhydroperoxide / Q000737:chemistry
chemical_list: D000480:Alkynes; D000814:Aniline Compounds; D007211:Indoles; D020122:tert-Butylhydroperoxide