meta-Selective C-H Arylation of Fluoroarenes and Simple Arenes
Luo-Yan Liu1, Jennifer X Qiao2, Kap-Sun Yeung3
1Department of Chemistry, The Scripps Research Institute (TSRI), 10550 North Torrey Pines Road, La Jolla, CA, 92037, USA.
Abstract:
Fluorine is known to promote ortho-C-H metalation. Based upon this reactivity, we employed an activated norbornene that traps the ortho-palladation intermediate and is then relayed to the meta position, leading to meta-selective C-H arylation of fluoroarenes. Deuterium experiment suggests that this meta-arylation is initiated by ortho C-H activation and the catalytic cycle is terminated by C-2 protonation. A dual-ligand system is crucial for the observed high reactivity and site selectivity. Applying this approach to simple benzene or other arenes also affords arylation products with good yield and site selectivity.
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