Zhao Jingjing, Li Pan, Xia Chungu, Li Fuwei
State Key Laboratory for Oxo Synthesis Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Science, Lanzhou 730000 (P. R. China).
Graduate University of Chinese Academy of Sciences, Beijing, 100049 (P. R. China).
Chemistry. 2015 Nov 9;21(46):16383-6. doi: 10.1002/chem.201503260. Epub 2015 Oct 2.
A mild and convenient synthesis of carbazoles by TfOTMS (trimethylsilyl trifluoromethanesulfonate)-catalyzed ring-opening annulation of 2-amidodihydrofurans is presented with a high degree of chemoselectivity and regioselectivity. This procedure was also scaled up to a gram-scale synthesis. The reaction could involve an iminonium intermediate through a series of C-O, C-N bond cleavages, C-C bond formations, and a 1,2-migration process.
