10.1021/acs.joc.9b00755.s006 Jing Qian Jing Qian Zhenwei Lin Zhenwei Lin Zaibin Wang Zaibin Wang Zhixing Peng Zhixing Peng Li Wu Li Wu Ping Lu Ping Lu Yanguang Wang Yanguang Wang Copper-Carbene-Triggered Electrophilic Cyclization of <i>o</i>‑Hydroxyarylenaminones with 3‑Diazoindolin-2-imines: Synthesis of 3‑Indolyl‑4<i>H</i>‑chromen-4-ones and Pyrido[2,3‑<i>b</i>:6,5‑<i>b</i>′]diindoles American Chemical Society 2019 solvent-dependent emission 3- diazoindolin -2-imines diindole photophysical properties substrate scope pyrazino Pyrido Copper-Carbene-Triggered Electrophilic Cyclization 3- indolyl -4 H chromen -4-ones 2019-04-19 00:00:00 Dataset https://acs.figshare.com/articles/dataset/Copper-Carbene-Triggered_Electrophilic_Cyclization_of_i_o_i_Hydroxyarylenaminones_with_3_Diazoindolin-2-imines_Synthesis_of_3_Indolyl_4_i_H_i_chromen-4-ones_and_Pyrido_2_3_i_b_i_6_5_i_b_i_diindoles/8059229 The Cu­(II)-catalyzed electrophilic cyclization reaction between <i>o</i>-hydroxyarylenaminones and 3-diazoindolin-2-imines furnished 3-indolyl-4<i>H</i>-chromen-4-ones in moderate to good yields with a broad substrate scope. Several pyrido­[2,3-<i>b</i>:6,5-<i>b</i>′]­diindoles and one pyrazino­[2,3-<i>b</i>:5,6-<i>b</i>′]­diindole were also obtained as byproducts in some cases and tested for their photophysical properties. Pyrido­[2,3-<i>b</i>:6,5-<i>b</i>′]­diindoles exhibited solvent-dependent emission, while pyrazino­[2,3-<i>b</i>:5,6-<i>b</i>′]­diindole emitted strong luminescence with 25.6% quantum yield in cyclohexane.