Triisopropyl borate → (4-Cyano-3-methylphenyl)boronic acid

HRID 1714820Notes

Reaction equation

HRID 1714820 reaction equation
C([Li])CCC.Br[C:7]1[CH:14]=[CH:13][C:10]([C:11]#[N:12])=[C:9]([CH3:15])[CH:8]=1.[B:16](OC(C)C)([O:21]C(C)C)[O:17]C(C)C>O1CCCC1>[C:11]([C:10]1[CH:13]=[CH:14][C:7]([B:16]([OH:21])[OH:17])=[CH:8][C:9]=1[CH3:15])#[N:12]

Participants

5

Reactant 3

HCID 21531Triisopropyl borateHCID 1442674-Bromo-2-methylbenzonitrileHCID 178418339Butyllithium

Product 1

HCID 53216294(4-Cyano-3-methylphenyl)boronic acid

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

10.21 ml of n-butyllithium solution (1.6M in hexane) are added dropwise to a solution of 3.00 g of 4-bromo-2-methylbenzonitrile in 50 ml of dry tetrahydrofuran at −78° C. after stirring at this temperature for 30 minutes, 4.22 ml of triisopropyl borate are added, and then the mixture is stirred at −78° C. for a further 45 minutes. 30 ml of 1N are added to the reaction mixture. The phases are separated and the aqueeous phase is extracted three more times with 100 ml of diethyl ether/tetrahydrofuran (1,1) each time. The combined organic phases are dried with sodium sulphate, filtered and concentrated to 4 ml in vacuo. The remaining oil is mixed with 100 ml of pentane, and the precipitate which has separated out is filtered off with suction and washed twice with penteane. Drying under high vacuum results in 1.82 g of the title compound as a white solid. Rt. 2.93.

Workup

  1. stirringthe mixture is stirred at −78° C. for a further 45 minutes
  2. addition30 ml of 1N are added to the reaction mixture
  3. customThe phases are separated
  4. extractionthe aqueeous phase is extracted three more times with 100 ml of diethyl ether/tetrahydrofuran (1,1) each time
  5. dry with materialThe combined organic phases are dried with sodium sulphate
  6. filtrationfiltered
  7. concentrationconcentrated to 4 ml in vacuo
  8. additionThe remaining oil is mixed with 100 ml of pentane
  9. customthe precipitate which has separated out
  10. filtrationis filtered off with suction
  11. washwashed twice with penteane
  12. customDrying under high vacuum

Sources & evidence

ORD record
ord-5043926cf808488285eb72e565e9e98a
Source dataset
uspto-grants-2010_09
Patent number
US07799779B2

Reaction notes

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