Regiodivergent Arylation of Pyridines via Zincke Intermediates
Haiwen Wang1, Michael F Greaney1
1School of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
Abstract:
An arylation protocol for pyridines is described, via the ring-opened Zincke intermediate. Treatment of pyridines with triflic anhydride and a secondary amine produces an azahexatriene species, which undergoes regioselective Pd-catalyzed arylation at the putative C4 position. Recyclization then provides the pyridine products. Alternatively, metal-free arylation with a diaryliodonium salt is selective for the pyridine meta-position, affording a regiodivergent approach to pyridine biaryls from a common intermediate.
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