Hydrogen Peroxide → 2-(((4-Chlorophenyl)sulfonyl)methyl)-1,4-difluorobenzene

Temperatur

0 °C

A mixture of sodium tungstate dihydrate (1.83 g, 5.54 mmol) as a solution in water (36.56 mL), 1M sulfuric acid (2.50 mL), 2-[[(4-chlorophenyl)thio]methyl]-1,4-difluorobenzene (Example 1) (10 g, 0.37 mol) and Aliquat 336™ (2.99 g, 7.39 mmol) in toluene (500 mL) was heated to 45° C., and 27.5% aqueous hydrogen peroxide (114.2 mL) was added slowly. The mixture was cooled and the unreacted peroxide was quenched by addition of 20wt % sodium metabisulfite solution (120 mL). The layers were separated. The organic phase was washed with water (190 mL) and concentrated to a total volume of approximately 200 mL. Heptane (400 mL) was added and the resulting mixture was cooled to 0° C. and filtered. The wet cake was washed with 2:1 heptane:toluene (200 mL) and then heptane (200 mL). The product was dried in vacuo at 40° C. to yield 107.6 g of 2-[[(4-chlorophenyl)sulfonyl]methyl]-1,4-difluorobenzene (96% yield). 1H NMR CDCl3— as obtained via Method (a).

1. temperatureThe mixture was cooled
2. customthe unreacted peroxide was quenched by addition of 20wt % sodium metabisulfite solution (120 mL)
3. customThe layers were separated
4. washThe organic phase was washed with water (190 mL)
5. concentrationconcentrated to a total volume of approximately 200 mL
6. additionHeptane (400 mL) was added
7. filtrationfiltered
8. washThe wet cake was washed with 2:1 heptane
9. customThe product was dried in vacuo at 40° C.

ORD-Eintrag

ord-c2f100396d4d4237b0810529ff13491e

Quelldatensatz

uspto-grants-2007_12

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07304094B2