4,4,5,5-tetraMethyl-2-[1,1':3',1''-terphenyl]-3-yl-1,3,2-dioxaborolane

98905-03-4

73183-34-3

1115023-84-1

3-Bromo-1,1':3',1''-terphenyl (26.60 g, 86.03 mmol, 1.0 eq.) and pinacol ester of biphenylboronic acid (103.23 g, 1.2 eq.) were added to a 1 L three-necked round-bottomed flask with potassium acetate (25.33 g, 3 eq.) and bis(diphenylphosphino)ferrocene(II) dichlorodichloromethane complex ( 2.11 g, 0.03 eq.). After the system was degassed and nitrogen displaced, 300 mL of cyclopentyl methyl ether was added under nitrogen atmosphere. Subsequently, the mixture was heated to 100 °C and refluxed with stirring. The heating was stopped after 3 h. The reaction mixture was extracted three times with toluene. The organic layers were combined, dried by adding anhydrous sodium sulfate and allowed to stand for a period of time. After removal of sodium sulfate by filtration, the solution was concentrated under reduced pressure. The oil obtained was purified by activated carbon column chromatography using toluene as eluent. The fraction containing the desired product 3-boronic acid pinacol ester-3′-phenyl-biphenyl was collected and concentrated under reduced pressure. The yellow oil obtained was dissolved in hot methanol and allowed to stand at room temperature before cooling in an ice bath. The precipitated needle-like crystals were collected to afford the target product P3Bpin (Yield: 28.48 g, Yield: 92.9%).