CuBr-Catalyzed Coupling of N-Tosylhydrazones and Terminal Alkynes: Synthesis of Benzofurans and Indoles
Lei Zhou, Yi Shi, Qing Xiao, Yizhou Liu, Fei Ye, Yan Zhang and Jianbo Wang
*Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China, Email: wangjbpku.edu.cn
L. Zhou, Y. Shi, Q. Xiao, Y. Liu, F. Ye, Y. Zhang, J. Wang, Org. Lett., 2011, 13, 968-971.
DOI: 10.1021/ol103009n (free Supporting Information)
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A ligand-free CuBr-catalyzed coupling/cyclization of terminal alkynes with N-tosylhydrazones derived from o-hydroxy- or o-aminobenzaldehydes enables the synthesis of benzofurans or indoles. A wide range of functional groups tolerate the reaction conditions.
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