反应详情

To a stirred solution of 4-chloro-2-fluoro-aniline (1.0 mL, 0.0090 mol) in benzene (50 mL) at room temperature under nitrogen was added in one portion neat iso-amyl nitrite (1.7 mL, 0.014 mol), and the mixture was slowly heated until gas evolution was observed (˜70° C.). The heat source was removed and the solution allowed to cool. After 10 minutes at room temperature, the mixture was heated to reflux, refluxed 2 hours and cooled. The solution was rotary evaporated to ˜3 mL and filtered through silica gel (100 g), eluting with hexanes. Fractions containing product were rotary evaporated, and the residue was rechromatographed on silica gel (50 g) eluting with n-hexane (20×50 mL) followed by n-hexane-diethyl ether (9:1, 10×50 mL) to give 0.875 g of 4-chloro-2-fluoro-biphenyl as a clear colorless oil; proton nuclear magnetic resonance spectroscopy (1H-NMR) (CDCl3): δ 7.36-7.53 (m, 6H), 7.18-7.22 (m, 2H).

1. temperaturethe mixture was slowly heated until gas evolution
2. custom(˜70° C.)
3. customThe heat source was removed
4. temperatureto cool
5. temperaturethe mixture was heated
6. temperatureto reflux
7. temperaturerefluxed 2 hours
8. temperaturecooled
9. customThe solution was rotary evaporated to ˜3 mL
10. filtrationfiltered through silica gel (100 g)
11. washeluting with hexanes
12. additionFractions containing product
13. customthe residue was rechromatographed on silica gel (50 g)
14. washeluting with n-hexane (20×50 mL)