Triisopropyl borate → 3-(2-Cyanopropan-2-yl)phenylboronic acid

HRID 216173Notes

Reaction equation

HRID 216173 reaction equation
Br[C:2]1[CH:3]=[C:4]([C:8]([CH3:12])([CH3:11])[C:9]#[N:10])[CH:5]=[CH:6][CH:7]=1.[B:13](OC(C)C)([O:18]C(C)C)[O:14]C(C)C.C([Li])(C)(C)C>C1(C)C=CC=CC=1.C1COCC1>[C:9]([C:8]([CH3:12])([CH3:11])[C:4]1[CH:3]=[C:2]([B:13]([OH:18])[OH:14])[CH:7]=[CH:6][CH:5]=1)#[N:10]

Participants

6

Reactant 3

HCID 21531Triisopropyl borateHCID 105132942-(3-Bromophenyl)-2-methylpropanenitrile2×HCID 178418306HCID 178418306, compound

Product 1

HCID 567766523-(2-Cyanopropan-2-yl)phenylboronic acidYield 120.2%

Reagents, catalysts & solvents 2

HCID 1140TolueneSolventHCID 8028TetrahydrofuranSolvent

Conditions

Temperature
-78 °C

Procedure

A solution of 2-(3-bromo-phenyl)-2-methyl-propionitrile [0.5 g, 2.2 mmol, Intermediate (65)] in toluene (8 mL) and THF (2 mL) is added triisopropyl borate (0.61 mL, 2.68 mmol) at −78° C. tert-Butyl lithium (1.7 M in pentane, 1.55 mL, 2.68 mmol) is added dropwise during 15 min. Reaction mixture is stirred at −78° C. for additional 1 hour, warmed up to −20° C. and quenched with 2N hydrochloric acid (10 mL). The reaction mixture is extracted with ether, combined ether layers are washed with brine, dried and concentrated to obtain 3-(cyano-dimethyl-methyl)-phenyl boronic acid (0.5 g) [Intermediate (66)] as an oil.

Workup

  1. additionis added dropwise during 15 min
  2. customReaction mixture
  3. temperaturewarmed up to −20° C.
  4. customquenched with 2N hydrochloric acid (10 mL)
  5. extractionThe reaction mixture is extracted with ether
  6. washare washed with brine
  7. customdried
  8. concentrationconcentrated

Sources & evidence

ORD record
ord-b28b83e5dd484d4f867db262d272ab70
Source dataset
uspto-grants-2012_06
Patent number
US08193183B2

Reaction notes

Loading…