Hydrochloric Acid → 4-(Difluoromethoxy)benzeneboronic acid

A solution of (4-bromophenoxy)difluoromethane (3 g) and triisopropyl borate (3.42 ml) in tetrahydrofuran (15 ml) was cooled to −78° C. under argon atmosphere, and thereto was added a solution of n-butyl lithium (1.59 M hexane solution, 3.42 ml). The mixture was stirred at room temperature overnight. Added thereto was 6N aqueous hydrochloric acid at 0° C., and the mixture was extracted with ethyl acetate. The extract was washed with brine, and dried over magnesium sulfate. The solvent was evaporated under reduced pressure, and the residue was triturated with cold hexane to give 4-(difluoromethoxy)phenylboronic acid (1.88 g) as colorless solid.

1. additionAdded
2. customat 0° C.
3. extractionthe mixture was extracted with ethyl acetate
4. washThe extract was washed with brine
5. dry with materialdried over magnesium sulfate
6. customThe solvent was evaporated under reduced pressure
7. customthe residue was triturated with cold hexane

ORD record

ord-c48a7fafa10c4192b77bef4e1a674121

Source dataset

uspto-grants-2012_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08202984B2