反应详情

Compound 5 (11.3 g, 45.54 mmol, 1 equiv) and iodopentafluorobenzene (10.6 g, 36.2 mmol, 1 equiv) were dissolved in toluene (200 mL) and 1.0M potassium carbonate solution (200 mL). Tetrabutylammonium bromide (1.6 g, 5 mmol, 0.11 equiv) was added and the solution sparged with nitrogen for 10 minutes. Tetrakis(triphenylphosphine)palladium(0) (2.63 g, 2.28 mmol, 0.05 equiv) was added and the reaction was refluxed for one day. The reaction was cooled to room temperature, then the layers were separated. The aqueous phase was back extracted with ethyl acetate (2×200 mL). Combined organic phases were combined, dried over sodium sulfate and concentrated under reduced pressure. The residue was purified over silica gel (200 g), eluting with heptanes to give 2,3,4,5,6-pentafluoro-2′-methoxy-5′-methyl-1,1′-biphenyl (6) (9.7 g, 74% yield) as a pale-yellow oil. This material contained a small amount of unreacted iodopentafluorobenzene which was identified by 19F NMR. The material was used subsequently.

1. customthe solution sparged with nitrogen for 10 minutes
2. temperaturethe reaction was refluxed for one day
3. customthe layers were separated
4. extractionThe aqueous phase was back extracted with ethyl acetate (2×200 mL)
5. dry with materialdried over sodium sulfate
6. concentrationconcentrated under reduced pressure
7. customThe residue was purified over silica gel (200 g)
8. washeluting with heptanes