Catalysis Based on C−I⋅⋅⋅π Halogen Bonds: Electrophilic Activation of 2‐Alkenylindoles by Cationic Halogen‐Bond Donors for [4+2] Cycloadditions
作者:Satoru Kuwano、Takumi Suzuki、Masahiro Yamanaka、Ryosuke Tsutsumi、Takayoshi Arai
DOI:10.1002/anie.201904689
日期:2019.7.22
Homo‐ and cross‐[4+2] cycloadditions of 2‐alkenylindoles, catalyzed by cationic halogen‐bond donors, were developed. Under mild reaction conditions, 3‐indolyl‐substituted tetrahydrocarbazole derivatives were obtained in good to excellent yields. Experimental and quantum calculation studies revealed that the electrophilic activation of 2‐alkenylindoles was achieved by C−I⋅⋅⋅π halogen bonds.
开发了由阳离子卤素键供体催化的2-烯基吲哚的均和环[4 + 2]环加成反应。在温和的反应条件下,可以很好地获得3-吲哚基取代的四咔唑衍生物。实验和量子计算研究表明,2-烯基吲哚的亲电活化是通过C−I⋅⋅⋅π卤素键实现的。