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Published on: November 9, 2019
Direct C4 Halogenation of Isoquinolines via a Boc2O-Mediated Dearomatization Strategy
Bingru Song1, Jiangtao Cai1, Dazhong Yuan1
1Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Materials Science, Zhejiang Normal University, 688 Yingbin Road, Jinhua 321004, P. R. China.
Abstract:
A cost-effective method for directly halogenating isoquinolines at the C4 position has been developed through a one-pot sequence involving Boc2O-mediated dearomatization, electrophilic halogenation (X = Cl, Br, I), and acid-promoted rearomatization. This reaction exhibited high C4 site selectivity, efficiently affording 4-halogenated isoquinolines, and demonstrated good functional group tolerance at C5-C8. In addition, the C-X bond-containing products could serve as versatile synthetic intermediates for further modification of isoquinolines, including Suzuki coupling, Sonogashira coupling, and Stille coupling.
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