Monobasic potassium phosphate → 4-Fluoro-3-nitropyridine

Anhydrous potassium fluoride (5.5 g, 93 mmol) was suspended in anhydrous dimethylsulfoxide (200 ml) and the solvent reduced to half its volume by distillation under an atmosphere of nitrogen. The resulting suspension was cooled to room temperature and 4-chloro-3-nitropyridine (14 g, 88 mmol) was added. The reaction mixture was stirred at 120° C. for three hours under an atmosphere of nitrogen, cooled and then poured into a saturated aqueous solution of potassium dihydrogen phosphate. The resulting mixture was extracted with ethyl acetate. The organic phase was washed three times with water and then brine before being dried over anhydrous magnesium sulphate. The solvent was removed in vacuo to yield as an oil, 4-fluoro-3-nitropyridine (6.5 g), (δ(CDCl3) 7.32 (1H, 4 lines), 7.86 (1H, t, J=5 Hz) and 8.29 (1H, d, J=9 Hz), represented by the structural formula: ##STR21##

1. distillationthe solvent reduced to half its volume by distillation under an atmosphere of nitrogen
2. temperaturecooled
3. extractionThe resulting mixture was extracted with ethyl acetate
4. washThe organic phase was washed three times with water
5. dry with materialbrine before being dried over anhydrous magnesium sulphate
6. customThe solvent was removed in vacuo

ORD-Eintrag

ord-0934ce69450b469a869b959ad0d0d886

Quelldatensatz

uspto-grants-1988_08

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US04761414