1400755-04-5

68120-35-4

73183-34-3

1400755-04-5

A mixture was prepared from 3-bromo-4-methylbenzyl alcohol (8.5 g, 42.2 mmol) and pinacol ester of bis(boronic acid) (11.8 g, 46.50 mmol) in 1,4-dioxane (50 mL) and degassed under nitrogen atmosphere for 10 min. Subsequently, potassium acetate (8.2 g, 84.55 mmol) and [1,1'-bis(diphenylphosphino)ferrocene]palladium(II) dichloride-CH2Cl2 (1.54 g, 2.11 mmol) were added to the mixture, and the reaction system was heated to 100 °C for 15 hours. Upon completion of the reaction, the solvent was removed by distillation under reduced pressure and the residue was diluted with water and extracted with ethyl acetate (2 x 150 mL). The organic phases were combined, washed sequentially with water and brine, dried over anhydrous sodium sulfate, filtered and concentrated. The crude product was purified by rapid chromatography on silica gel (ethyl acetate:hexane = 70:30) to afford the target product (4-methyl-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)methanol as a brown liquid (5.0 g, 84% yield). The structure of the product was confirmed by 1H NMR (400 MHz, DMSO-d6): δ 7.59 (d, J = 1.72 Hz, 1H), 7.25 (dd, J = 7.76, 1.88 Hz, 1H), 7.11 (d, J = 7.76 Hz, 1H), 5.10 (t, J = 5.72 Hz, 1H), 4.43 (d, J = 5.72 Hz, 2H), 2.42 (s, 3H), 1.29 (s, 12H).