反应详情

To a suspension of 2-fluoro-4-methylaniline (2.0 g, 16 mmol) in aqueous sulfuric acid (˜7 N) was added an aqueous solution of sodium nitrite (1.10 g, 16 mmol, 10 mL water) dropwise at 0° C. and the resulting light orange solution was stirred for 30 minutes. This solution was carefully poured into an aqueous solution of potassium iodide (3.98 g, 24 mmol, 16 mL water) at 80° C. and the resulting red mixture was stirred 1.5 hours at 80° C., and overnight at 50° C. The reaction was cooled to room temperature, poured into water (300 mL), and sodium bisulfite added until the light yellow color remained constant. The aqueous was extracted with diethyl ether (2×125 mL) and the organics were combined, washed with brine, dried (sodium sulfate), filtered, and the ether evaporated to give 2.5 g (66%) of crude product as a yellow green oil. Used without further purification. 1H NMR (CDCl3) δ2.32 (s, 3H,), 6.72 (dd, 1H, J=1.28 Hz, J=8.05 Hz), 6.88 (dd, 1H, J=1.28 Hz, JH=8.97 Hz), 7.58 (dd, 1H, J=1.08 Hz, J=6.78 Hz).

1. stirringthe resulting red mixture was stirred 1.5 hours at 80° C.
2. customovernight
3. customat 50° C
4. additionadded until the light yellow color
5. extractionThe aqueous was extracted with diethyl ether (2×125 mL)
6. washwashed with brine
7. dry with materialdried (sodium sulfate)
8. filtrationfiltered
9. customthe ether evaporated