Hydrochloric Acid → 4-Chloro-3-(difluoromethoxy)phenylboronic acid

2 M hydrochloric acid (10 mL) was added to the crude product of 2-(4-chloro-3-difluoromethoxyphenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (1.14 g) in tetrahydrofuran (10 mL), and the mixture was stirred at room temperature for four hours. Water and ethyl acetate were added to the reaction solution, followed by extraction with ethyl acetate. The organic layer was extracted with a 2 M sodium hydroxide solution. The resulting solution was made acidic with concentrated hydrochloric acid and then extracted with ethyl acetate. The organic layer was dried over anhydrous magnesium sulfate and filtered. The filtrate was concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography (hexane:ethyl acetate=99:1→50:50) to give the title compound (93 mg).

1. extractionfollowed by extraction with ethyl acetate
2. extractionThe organic layer was extracted with a 2 M sodium hydroxide solution
3. extractionextracted with ethyl acetate
4. dry with materialThe organic layer was dried over anhydrous magnesium sulfate
5. filtrationfiltered
6. concentrationThe filtrate was concentrated under reduced pressure
7. customThe resulting residue was purified by silica gel column chromatography (hexane:ethyl acetate=99:1→50:50)

ORD record

ord-921282412fbb489f970227b3c909b186

Source dataset

uspto-grants-2014_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08822503B2