Potassium hydroxy sulfite → 1261604-72-1

Temperature

0 °C

To a solution of 4-bromo-2-chloro-1-(difluoromethoxy)benzene (Preparation 27, 0.83 g, 3.2 mmol) in THF (16 ml) was added 4,4,4′,4′,5,5,5′,5′-octamethyl-2,2′-bi-1,3,2-dioxaborolane (0.90 g, 3.6 mmol), Pd(dppf)Cl2 (0.12 g, 0.16 mmol), and potassium acetate (0.98 g, 9.7 mmol) under N2 and the resulting mixture was heated to reflux for 2 hours. The reaction mixture was concentrated in vacuo and the residue filtered through a silica gel cake with arbocel on top washing through with EtOAc. The filtrate was concentrated in vacuo to give a crude product of 2-[3-chloro-4-(difluoromethoxy)phenyl]-4,4,5,5-tetramethyl-1,3,2-dioxaborolane. A solution of crude of 2-[3-chloro-4-(difluoromethoxy)phenyl]-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (1.0 g, 3.3 mmol) in acetone (10 ml) was added to an aqueous oxone solution (2.6 g, 3.9 mmol, 10 mL) dropwise with stirring at 0° C. for 1 hour. The reaction mixture was partitioned between water (20 ml) and EtOAc (20 ml), the combined organic phase was washed with brine, dried over sodium sulphate, filtered, and concentrated in vacuo to give a crude product, which was purified by silica gel chromatography eluting with 0-40% EtOAc in Heptane to afford the title compound (0.53 g, 82% yield) as a pale brown oil.

1. customThe reaction mixture was partitioned between water (20 ml) and EtOAc (20 ml)
2. washthe combined organic phase was washed with brine
3. dry with materialdried over sodium sulphate
4. filtrationfiltered
5. concentrationconcentrated in vacuo
6. customto give a crude product, which
7. customwas purified by silica gel chromatography
8. washeluting with 0-40% EtOAc in Heptane

ORD record

ord-57a46bc889694e06858af4eab1b5d1f2

Source dataset

uspto-grants-2014_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08685977B2