2-Bromo-1-fluoro-4-nitrobenzene → 2-Fluoro-2'-methylthio-5-nitrobiphenyl

Temperatur

50 °C

A mixture of 2-bromo-1-fluoro-4-nitrobenzene (5.89 g, 26.8 mmol), 2-(methylthio)benzeneboronic acid (5.62 g, 33.5 mmol) and potassium fluoride (5.13 g, 88.3 mmol) in tetrahydrofuran (70 ml) was degassed with nitrogen for 30 min. This mixture was then treated with tris(dibenzylideneacetone)dipalladium(0) (496 mg, 0.541 mmol) followed by tri-tert-butylphosphine (5.35 ml of a 0.2M solution in 1,4-dioxane, 1.07 mmol) and the reaction was degassed for a further 10 min. The resulting slurry was then heated at 50° C. for 16 h under nitrogen. After cooling, the reaction mixture was partitioned between ethyl acetate (300 ml) and water (300 ml). The organic layer was washed with brine (200 ml), dried over anhydrous sodium sulphate, filtered and evaporated. Purification by chromatography on silica gel eluting with isohexane on a gradient of ethyl acetate (5-10%) gave 2-fluoro-2′-methylthio-5-nitrobiphenyl as a pale yellow solid (6.95 g, 99%): δH (360 MHz, CDCl3) 2.42 (3H, s), 7.21-7.32 (3H, m), 7.37 (1H, d, J 7), 7.44 (1H, td, J 8 and 2), 8.27-8.31 (2H, m).

1. customwas degassed with nitrogen for 30 min
2. customwas degassed for a further 10 min
3. temperatureAfter cooling
4. customthe reaction mixture was partitioned between ethyl acetate (300 ml) and water (300 ml)
5. washThe organic layer was washed with brine (200 ml)
6. dry with materialdried over anhydrous sodium sulphate
7. filtrationfiltered
8. customevaporated
9. customPurification by chromatography on silica gel eluting with isohexane on a gradient of ethyl acetate (5-10%)

ORD-Eintrag

ord-470160545f924e8b899f18ebf57b2570

Quelldatensatz

uspto-grants-2005_05

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US06900215B2