反应详情

18.5 g (0.1 mole) of 3,3-dimethyl-4-fluoro-1-(1,2,4-triazol-1-yl)-butan-2-one were dissolved in 150 ml of glacial acetic acid, and, after adding 8.2 g (0.1 mole) of sodium acetate, 16 g (0.1 mole) of bromine were added dropwise at 45° C., until the mixture was completely decolorized. The mixture was then poured into ice-water and extracted with chloroform. The combined chloroform extracts were washed with sodium bicarbonate solution, dried over magnesium sulphate and concentrated. The oily 1-bromo-3,3-dimethyl-4-fluoro-1-(1,2,4-triazol-1-yl)-butan-2-one which remained was dissolved in 50 ml of acetonitrile, and 11.3 g (0.1 mole) of 6-fluoro-2-hydroxy-pyridine and 10.5 g (0.1 mole) of triethylamine, both dissolved in 120 ml of acetonitrile, were added, while stirring. The mixture was stirred under reflux for 1 hour. It was then concentrated by distilling off the solvent in vacuo, and the residue was stirred with water. The crystalline precipitate formed was filtered off and recrystallized from cyclohexane. 20 g (68% of theory) of 3,3-dimethyl-4-fluoro-1-(6-fluoro-pyridin-2-yl-oxy)-1-(1,2,4-triazol-1-yl)-butan-2-one of melting point 116° C. were obtained.

1. additionwere added dropwise at 45° C., until the mixture
2. extractionextracted with chloroform
3. washThe combined chloroform extracts were washed with sodium bicarbonate solution
4. dry with materialdried over magnesium sulphate
5. concentrationconcentrated
6. dissolutionThe oily 1-bromo-3,3-dimethyl-4-fluoro-1-(1,2,4-triazol-1-yl)-butan-2-one which remained was dissolved in 50 ml of acetonitrile
7. additionwere added
8. stirringThe mixture was stirred
9. temperatureunder reflux for 1 hour
10. concentrationIt was then concentrated
11. distillationby distilling off the solvent in vacuo
12. stirringthe residue was stirred with water
13. customThe crystalline precipitate formed
14. filtrationwas filtered off
15. customrecrystallized from cyclohexane