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1. Synthesis of (racemic)-6-bromo-2,3-dihydrobenzofuran-3-ol To a solution of 6-bromo-3-benzofuranone (10.5 g, 49.28 mmol) in methanol (100 mL) was slowly added sodium borohydride (2.37 g, 64.07 mmol) at 0 °C. Subsequently, the reaction mixture was stirred at room temperature for 2 hours. Upon completion of the reaction, the reaction was quenched with saturated ammonium chloride solution (50 mL) and extracted twice with ethyl acetate (2 x 50 mL). The organic phases were combined, dried over anhydrous sodium sulfate and concentrated under reduced pressure to give the product 6-bromo-2,3-dihydrobenzofuran-3-ol (9.75 g, 92% yield) as a colorless liquid.

[1] Patent: WO2012/101011, 2012, A2. Location in patent: Page/Page column 56
[2] Patent: US2013/18055, 2013, A1. Location in patent: Paragraph 0331-0332