title: [3 + 2]-Annulations of N-alkyl-3-substituted indoles with quinone monoketals catalysed by Brønsted acids.
abstract: An organocatalytic dearomative [3 + 2]-annulation of N-alkyl-3-alkylindoles with quinone monoketals is developed. The reaction provides a mild and straightforward way to various benzofuro[2,3-b]indolines of potential biological and pharmaceutical interest in moderate to good yields. Moreover, when 3-phenylindole, a problematic substrate in previous relevant studies, was used as the substrate under the otherwise same reaction conditions, a novel 1,2-shift of the phenyl group occurred followed by aromatization to provide 2,3-diaryl indoles useful for cancer therapy studies in moderate yields.
authors.affiliation: Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Laboratory of Molecule-Based Materials, Institute of Organic Chemistry, School of Chemistry and Materials Science, Anhui Normal University, Wuhu, Anhui 241000, China. chaizhuo@mail.ahnu.edu.cn gshyang@mail.ahnu.edu.cn.
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Chai
authors.forename: Jia-Nan
authors.initials: JN
authors.lastname: Chen
authors.forename: Zhen
authors.initials: Z
authors.lastname: Liu
authors.forename: Xue-Fei
authors.initials: XF
authors.lastname: Li
authors.forename: Pei-Jun
authors.initials: PJ
authors.lastname: Yang
authors.forename: Ji-Ping
authors.initials: JP
authors.lastname: Hu
authors.forename: Gaosheng
authors.initials: G
authors.lastname: Yang
mesh_terms: D000143:Acids / Q000737:chemistry*; D016227:Benzoquinones / Q000737:chemistry*; D002384:Catalysis; D003500:Cyclization; D007211:Indoles / Q000138:chemical synthesis* / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure
chemical_list: D000143:Acids; D016227:Benzoquinones; D007211:Indoles; C004532:quinone