Triisopropyl borate → 4-(2-(Tetrahydro-2H-pyran-2-yloxy)ethoxy)-3-(trifluoromethyl)phenylboronic acid

HRID 912512Notes

Reaction equation

[Li]CCCC.Br[C:7]1[CH:22]=[CH:21][C:10]([O:11][CH2:12][CH2:13][O:14][CH:15]2[CH2:20][CH2:19][CH2:18][CH2:17][O:16]2)=[C:9]([C:23]([F:26])([F:25])[F:24])[CH:8]=1.[B:27](OC(C)C)([O:32]C(C)C)[O:28]C(C)C>C1COCC1>[O:16]1[CH2:17][CH2:18][CH2:19][CH2:20][CH:15]1[O:14][CH2:13][CH2:12][O:11][C:10]1[CH:21]=[CH:22][C:7]([B:27]([OH:32])[OH:28])=[CH:8][C:9]=1[C:23]([F:26])([F:25])[F:24]

Participants

Conditions

Temperature: -78 °C

Procedure

BuLi (2.5M, 6 ml) was added dropwise to a solution of 2-(2-(4-bromo-2-(trifluoromethyl)phenoxy)ethoxy)tetrahydro-2H-pyran (5 g) in THF (50 ml) at −78° C. under N2 during 3 minutes. After stirring at −78° C. for another 10 minutes, triisopropyl borate (3.8 ml) was then added dropwise during 2 minutes at −78° C. The mixture was stirred at −78° C. for further 30 minutes, then slowly warmed up to room temperature and stirred at room temperature for 30 minutes. The mixture was then quenched with acetic acid (10% in water, 20 ml), extracted with EtOAc (300 ml), washed with water (200 ml×3), dried over sodium sulphate, solvent removed under reduced pressure, the residue was taken in to toluene and then solvent removed under reduced pressure to take out traces of acetic acid (repeat 3 times) (4.5 g).

Workup

stirringThe mixture was stirred at −78° C. for further 30 minutes
temperatureslowly warmed up to room temperature
stirringstirred at room temperature for 30 minutes
customThe mixture was then quenched with acetic acid (10% in water, 20 ml)
extractionextracted with EtOAc (300 ml)
washwashed with water (200 ml×3)
dry with materialdried over sodium sulphate, solvent
customremoved under reduced pressure
customsolvent removed under reduced pressure

Sources & evidence

ORD record: ord-3f55f8954af14e8a98c6957c10ce4b39
Source dataset: uspto-grants-2011_09
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08026236B2

Reaction notes

Loading…