Iron-Catalyzed C3-Formylation of Indoles with Formaldehyde and Aqueous Ammonia under Air
Qing-Dong Wang, Bin Zhou, Jin-Ming Yang*, Dong Fang, Jiangmeng Ren, Bu-Bing Zeng*
*Yancheng Teachers University, Yancheng, Jiangsu 224007; East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P. R. of China, Email: chemyjm163.com, zengbbecust.edu.cn
Q.-D. Wang, B. Zhou, J.-M. Yang, D. Fang, J. Ren, B.-B. Zeng, Synlett, 2017, 28, 2670-2674.
DOI: 10.1055/s-0036-1589079 (free Supporting Information)
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An efficient iron-catalyzed C3-selective formylation of free or N-substituted provides 3-formylindoles in good yields in fairly short reaction times in the presence of formaldehyde and aqueous ammonia, with air as the oxidant. Moreover, this catalytic formylation of indoles can be applied to gram-scale syntheses.
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