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Scalable Electrochemical Dehydrogenative Lactonization of C(sp2/sp3)-H Bonds
Sheng Zhang1, Lijun Li1, Huiqiao Wang1
1College of Chemistry and Pharmaceutical Engineering, Nanyang Normal University , Nanyang 473061, China.
Abstract:
A practical, electrochemical method is developed for the direct dehydrogenative lactonization of C(sp2/sp3)-H bonds under external oxidant- and metal-free conditions, delivering diverse lactones, including coumarin derivatives with excellent regioselectivity. The scalable nature of this newly developed electrochemical process was demonstrated on a 40 g scale following an operationally simple protocol. The remote lactonization of C(sp3)-H bonds would constitute an important synthetic advance toward electrochemical C-O bond formation.
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