I2-Catalyzed Oxidative Coupling Reactions of Hydrazones and Amines and the Application in the Synthesis of 1,3,5-Trisubstituted 1,2,4-Triazoles
Zhengkai Chen*, Hongli Li, Weipeng Dong, Maozhong Miao and Hongjun Ren*
*Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China, Email: zkchenzstu.edu.cn, renhjzstu.edu.cn
Z. Chen, H. Li, W. Dong, M. Miao, H. Ren, Org. Lett., 2016, 18, 1334-1337.
DOI: 10.1021/acs.orglett.6b00277 (free Supporting Information)
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A general and metal-free synthesis of 1,3,5-trisubstituted 1,2,4-triazoles from hydrazones and aliphatic amines has been achieved under oxidative conditions via a cascade C-H functionalization, double C-N bonds formation, and oxidative aromatization sequence in the presence of iodine as catalyst.
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If the reaction is performed under N2 atmosphere, a slight decrease of the yield is observed. We speculated that O2 could partially participate in the oxidation process.
Zhengkai Chen, February 2, 2017