Cascade hydroarylation/Diels-Alder cycloaddition of alkynylindoles with electron-deficient alkynes and alkenes
Guang-Chao Feng1, Jun-Chi Li1, Xiang Huang1
1School of Pharmaceutical Sciences, South-Central Minzu University, Wuhan 430074, People's Republic of China. jmyang@scuec.edu.cn.
Abstract:
Herein, a novel cascade gold(I)-catalyzed hydroarylation of alkynylindoles and subsequent Diels-Alder cycloaddition with electron-deficient alkynes and alkenes is described. A variety of azepino-fused hydrocarbazoles and carbazoles were obtained in moderate to excellent yields. Key features of this methodology are low catalyst loadings, high regioselectivity, broad functional group tolerances, access to important heterocycles, and 100% atom economy.
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