13420-63-8

The following building block was synthesized via a C-H activation method developed by Yu and coworkers. The method was incorporated using the Yu-Wasa Auxiliary (Aldrich 791806) and I₂ as the sole oxidant for ortho-iodination from the corresponding benzoic acid derivative.

reagent type: ligand
reaction type: C-H Activation

General procedure: In a flame-dried 100 mL round-bottomed flask, 2-chlorobenzoic acid (16.4 mmol, 1.0 eq.), palladium acetate (0.05 eq.), iodobenzene diacetate (1.5 eq.), and iodine (1.5 eq.) were added and dissolved in anhydrous DMF (40 mL), and the reaction system was kept at atmospheric conditions. After sealing the flask with a rubber septum, the reaction mixture was stirred at 100 °C for 24 hours. Upon completion of the reaction, the mixture was cooled to room temperature, diluted with ethyl acetate and subsequently washed with 0.5 N HCl solution (420 mL). The organic phase was washed with saturated brine, dried over anhydrous sodium sulfate and finally concentrated in a rotary evaporator. The crude product was purified by silica gel column chromatography (eluent ratio 3:1 hexane/ethyl acetate) to afford the target product 2-chloro-6-iodobenzoic acid.

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