4-Bromobiphenyl → 1,1'-Biphenyl-4-yl-boronic acid

4-Biphenylboronic acid was prepared differently than described in the literature (see Yabroff, D. L.; Branch, G. E.; Bettman, B. J. Am. Chem. Soc. 1934, 56, 1850-1857). To a solution of 4-bromobiphenyl (2.00 g, 8.58 mmol) in THF (20 mL) at −78° C. was added n-butyllithium (4.0 mL of 2.5 M in hexanes) in a slow stream via syringe. After 15 minutes, triisopropylborate (3.0 mL, 13 mmol) was added in a slow stream via syringe. After 10 minutes, the resultant homogeneous solution was allowed to warm to ambient temperature over 45 minutes and partitioned between EtOAc (50 mL) and 10% aqueous HCl (50 mL). The aqueous layer was separated and extracted with more EtOAc. The combined organic layers were washed with brine, dried over Na2SO4 and concentrated to give a crude product which was triturated with hexanes to yield 1.53 g (90%) of 4-biphenylboronic acid as a white solid. 1H NMR (DMSO-d6): δ 8.05 (s, 2H), 7.83 (d, 2H, J=8.5 Hz), 7.65 (d, 2H, J=7.0 Hz), 7.60 (d, 2H, J=8.1 Hz), 7.43 (t, 2H, J=7.4 Hz), 7.33 (t, 1H, J=7.2 Hz). Anal. C12H11BO2: C, 72.78; H, 5.60 Found: C, 72.51; H, 5.62.

1. waitAfter 10 minutes
2. custompartitioned between EtOAc (50 mL) and 10% aqueous HCl (50 mL)
3. customThe aqueous layer was separated
4. extractionextracted with more EtOAc
5. washThe combined organic layers were washed with brine
6. dry with materialdried over Na2SO4
7. concentrationconcentrated
8. customto give a crude product which

ORD record

ord-8bdeca10b8654a3a8c27d8415355e050

Source dataset

uspto-grants-2002_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06495699B2