890839-37-9

406482-20-0

General procedure for the synthesis of 2,6-difluoro-4-methoxyphenylboronic acid from 2-(3,5-difluoro-4-methoxyphenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) anisole: To an acetone solution of 2,6-difluoro-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) anisole (0.88 g. 15 mL) was added to an aqueous ammonium acetate solution (18 mL, 1 mol/L aqueous solution) and sodium metaiodate (2.6 g). The reaction mixture was stirred at room temperature overnight. Upon completion of the reaction, the mixture was concentrated, diluted with water and extracted with ethyl acetate. The organic phases were combined, dried with sodium sulfate and concentrated under reduced pressure to remove the solvent. The crude product was purified by silica gel column chromatography with the eluent cyclohexane/ethyl acetate (1:0→1:1). The target product 2,6-difluoro-4-methoxyphenylboronic acid was obtained in a yield of 0.27 g in 44%.