title: Regio- and Enantioselective Aza-Diels-Alder Reactions of 3-Vinylindoles: A Concise Synthesis of the Antimalarial Spiroindolone NITD609.
abstract: An asymmetric aza-Diels-Alder reaction of 3-vinylindoles with isatin-derived ketimines has been developed. A series of spiroindolone derivatives were thus obtained in good to excellent yields with excellent enantioselectivity (up to 96 % yield and 99 % ee). Furthermore, the antimalarial compound NITD609 could be obtained in three steps with an overall yield of 40.6 %. Control experiments and operando IR experiments imply a concerted reaction pathway. The regioselectivity and exo selectivity result from π-π interactions between the two indoline rings of the two reactants.
authors.affiliation: Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064 (China).
authors.forename: Haifeng
authors.initials: H
authors.lastname: Zheng
authors.affiliation: Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064 (China). liuxh@scu.edu.cn.
authors.forename: Xiaohua
authors.initials: X
authors.lastname: Liu
authors.affiliation: Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064 (China).
authors.forename: Chaoran
authors.initials: C
authors.lastname: Xu
authors.affiliation: Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064 (China).
authors.forename: Yong
authors.initials: Y
authors.lastname: Xia
authors.affiliation: Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064 (China).
authors.forename: Lili
authors.initials: L
authors.lastname: Lin
authors.affiliation: Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064 (China). xmfeng@scu.edu.cn.|Collaborative Innovation Center of Chemical Science and Engineering Tianjin (China). xmfeng@scu.edu.cn.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Feng
mesh_terms: D000962:Antimalarials / Q000737:chemistry*; D007211:Indoles / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D000962:Antimalarials; D007211:Indoles
keywords: asymmetric catalysis; aza-Diels-Alder reactions; indoles; ketimines; nickel catalysis