Photochemical α-carboxyalkylation of tryptophols and tryptamines via C-H functionalization
Zhiqiang Pan1, Yuchang Liu, Fengchi Hu
1Key Laboratory of Medicinal Chemistry for Natural Resource (Ministry of Education and Yunnan Province), School of Chemical Science and Technology, Yunnan University, Kunming, Yunnan 650091, China. xiacf@ynu.edu.cn.
Abstract:
A process for the α-carboxyalkylation of tryptophols and tryptamines by the functionalization of C-H bonds under visible light irradiation has been developed. The photochemical strategy activated the C-Br bonds of α-bromo-alkylcarboxylic esters to provide carbon-centered radicals under the catalysis of Ir(iii) photocatalyst and coupled with indole derivatives. This methodology displayed wide functional group tolerance and excellent regioselectivity, and was applied to the late-stage functionalization and preparation of indole-containing hybrids.
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