Synthesis of 4-Halogenated 3-Fluoro-6-methoxyquinolines: Key Building Blocks for the Synthesis of Antibiotics

Abstract

A practical and scalable 4-step route is presented for the synthesis of 4-bromo-3-fluoro-6-methoxyoquinoline and 3-fluoro-4-iodo-6-methoxyoquinoline from readily available 2,4-dichloro-3-fluoroquinoline with an overall yield of 81–85%. Halogenated quinoline building blocks have found much use in antimicrobial drug discovery, and the method reported here would be useful for the synthesis of these compounds.

Key words

antibiotic - quinolone - fluorine - heterocycle - regioselectivity

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