Water → B-(4-(2-Pyridinyl)phenyl)boronic acid

HRID 2392662Notes

Reaction equation

HRID 2392662 reaction equation
C([Li])CCC.Br[C:7]1[CH:12]=[CH:11][C:10]([C:13]2[CH:18]=[CH:17][CH:16]=[CH:15][N:14]=2)=[CH:9][CH:8]=1.C([O:22][B:23](OC(C)C)[O:24]C(C)C)(C)C.O>CCOCC>[N:14]1[CH:15]=[CH:16][CH:17]=[CH:18][C:13]=1[C:10]1[CH:11]=[CH:12][C:7]([B:23]([OH:24])[OH:22])=[CH:8][CH:9]=1

Participants

6

Reactant 4

HCID 962WaterHCID 21531Triisopropyl borateHCID 15152372-(4-Bromophenyl)pyridineHCID 178418339Butyllithium

Product 1

HCID 18980112B-(4-(2-Pyridinyl)phenyl)boronic acidYield 18%

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent2×

Conditions

Temperature
-20 °C

Procedure

n-Butyllithium (1.6M in hexane, 2.67 ml) was added to dry ether (16 ml) at -78° C. under argon. A solution of 2-(4-bromophenyl)pyridine (D76, 1.0 g) in dry ether (20 ml) was added dropwise over 5 minutes and allowed to warm to -20° C. for approximately 2 minutes to give a deep red solution. After recooling to -78° C., triisopropylborate (1.18 ml) was added, stirred 30 minutes, warned to ambient temperature to give a yellow cloudy mixture. Water (4.2 ml) and 0.5 MNaOH (4.2 ml) were added with vigorous stirring and the mixture separated. The ether layer was extracted with 0.5M NaOH (2.8 ml) and the combined aqueous extracts were extracted with ether (2×30 ml). The aqueous layer was acidified to pH6 with dilute hydrochloric acid to give the title compound as a beige solid, (0.15 g, 18%).

Workup

  1. customto give a deep red solution
  2. customAfter recooling to -78° C.
  3. customwarned to ambient temperature
  4. customto give a yellow cloudy mixture
  5. stirringwith vigorous stirring
  6. customthe mixture separated
  7. extractionThe ether layer was extracted with 0.5M NaOH (2.8 ml)
  8. extractionthe combined aqueous extracts were extracted with ether (2×30 ml)

Sources & evidence

ORD record
ord-b3950d0bc9244846a1c7ec6940b614c6
Source dataset
uspto-grants-1998_09
Patent number
US05801170

Reaction notes

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