反应详情

Potassium tert-butoxide (3.5 g, 31 mmol) was added to a solution of 4-amino-3-fluoro-2-methyl-phenol (4.2 g, 30 mmol) in dimethylacetamide. The mixture was stirred at RT for 30 min. A solution of 2,4-dichloropyridine (4.38 g, 30 mmol) in dimethylacetamide was added and the mixture was heated at 100° C. overnight. The reaction mixture was concentrated in vacuo and the residue was dissolved in ethyl acetate (200 mL) and filtered through silica gel. The filter cake was washed with ethyl acetate, the combined filtrates were concentrated in vacuo and purified by silica gel chromatography to give 4-(2-chloro-pyridin-4-yloxy)-2-fluoro-3-methyl-phenylamine (3.2 g, 42% yield). 1H NMR (400 MHz, DMSO-d6): δ 8.21 (d, J=6.4 Hz, 1H), 6.84 (d, J=2.0 Hz, 1H), 6.81 (dd, J=5.6, 2.4 Hz, 1H), 6.67-6.65 (m, 2H), 5.13 (s, 2H), 1.91 (s, 3H); MS (ESI): m/z 253.2 [M+H]+.

1. temperaturethe mixture was heated at 100° C. overnight
2. concentrationThe reaction mixture was concentrated in vacuo
3. dissolutionthe residue was dissolved in ethyl acetate (200 mL)
4. filtrationfiltered through silica gel
5. washThe filter cake was washed with ethyl acetate
6. concentrationthe combined filtrates were concentrated in vacuo
7. custompurified by silica gel chromatography