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DOI: 10.1055/sos-SD-120-00214

Sawamura, M.; Shimizu, Y.Science of Synthesis Knowledge Updatesearly view.

Carboxy-group-directed C(sp2)H iodination can provide aryl iodides, which are useful substrates for a wide range of coupling reactions. Acetyl hypoiodite (AcOI), generated in situ by the rapid reaction between (diacetoxyiodo)benzene and molecular iodine, is an active iodination reagent in the presence of palladium(II) acetate as catalyst, in dimethylformamide at 60°C (Scheme 33).[‌74‌] Keeping the reaction system in the dark is important to avoid an unwanted decarboxylation reaction taking place. The catalysis provides monoiodination products 62 exclusively, with iodination taking place at the sterically less hindered ortho position. The palladium catalyst can be reused at least five times by recycling the precipitated palladium(II) iodide by centrifugation for the next reaction.

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