Thermal-mediated [1,3]-hydrogen transfer as the key step: access to oxindole-chromone hybrid collection with
Yi Gong1, Sheng-Wen Xu2, Xiong-Wei Liu2
1College of Pharmaceutical Sciences, Guizhou University of Traditional Chinese Medicine, Guiyang, Guizhou 550025, P. R. China. xlliu1@gzu.edu.cn yzhou@gzu.edu.cn and Guizhou Engineering Center for Innovative Traditional Chinese Medicine and Ethnic Medicine, Guizhou University, Guiyang, Guizhou 550025, P. R. China.
Abstract:
Inspired by the chemistry and biology of chromone and oxindole derivatives, herein we report the first example of thermal-mediated [1,3]-hydrogen transfer as the key step for the efficient synthesis of oxindole-chromone hybrid collections 2, which avoids additional catalyst and solvent conditions. All the oxindole-chromones 2 are smoothly obtained in >99% yields in all cases, avoiding column chromatography purification. In particular, the products 2 can act as potential synthons for further elaboration in structural diversity, which might be valuable in organic and medicinal chemistry.
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