Mechanochemical Intramolecular C(sp3)-H/C(sp2)-H Coupling for Synthesis of Acridine and Anthracene Skeletons
Clement Jun Li Ong1, Hui Han1, Ivan Han Zhe Koa1
1School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 21 Nanyang Link, Singapore 637371, Singapore.
Abstract:
Direct C-H/C-H coupling represents an attractive strategy for efficient carbon-carbon bond formation; however, the selective activation of unactivated C-H bonds remains a significant challenge. Here we report a mechanochemical approach to intramolecular C(sp3)-H/C(sp2)-H coupling using a potassium/ferrocene system, enabling the rapid synthesis of acridine and anthracene frameworks from unactivated substrates within 30 min of ball milling. The results reveal a unique interplay between alkali metals and ferrocene and provides a new platform for C(sp3)-H/C(sp2)-H coupling.
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