133720-60-2

1-Bromo-2-(2,2-diethoxyethoxy)benzene (0102-3) (3.33 g, 11.56 mmol, 1.0 eq.) was used as a feedstock and dissolved in dichloroethane (DCE) (60 mL). Subsequently, polyphosphoric acid (PPA) (11.72 g, 34.68 mmol, 3.0 equiv) was added. The air in the round-bottomed flask was displaced three times by nitrogen, and then the reaction was refluxed for 3 h at 83 °C. After completion of the reaction, dichloromethane (100 mL) was added to the reaction mixture and washed with deionized water (100 mL x 3). The organic phase was dried with anhydrous sodium sulfate and subsequently concentrated. Finally, purification by silica gel column chromatography (eluent: 100% petroleum ether) afforded the light yellow solid product 7-bromobenzofuran (1.336 g, yield: 58%).

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