反应详情

(E)-2-phenylethensulfonyl chloride (381 mg) and dimethylaminopyridine (77 mg) were added at room temperature under an atmosphere of nitrogen to a solution of 2-{[5-amino-4-(1,3-benzodioxol-5-yl)-1-methyl-1H-pyrazol-3-yl]oxy}-1-ethanol (200 mg) (Preparation 45) in anhydrous pyridine (6 ml). After 24 h, the mixture was concentrated under reduced pressure. To the yellow solid was added water (30 ml), an aqueous solution of HCl (1N) to acidify the solution and the mixture was extracted with dichloromethane (3×30 ml). The organic fractions were combined, dried on sodium sulfate and concentrated under reduced pressure. The residue was dissolved in ethanol (6 ml) and dichloromethane (1 ml) and an excess of an aqueous solution of sodium hydroxyde (2N) was added. The reaction was stirred overnight. The reaction mixture was then diluted with dichloromethane (100 ml), acidified with an aqueous solution of HCl (1N). The phases were separated and the aqueous phase was extracted with dichloromethane (2×50 ml). The combined organic fractions were dried on sodium sulfate and concentrated under reduced pressure. The residue was purified by column chromatography (silica, 20 g) eluted with dichloromethane:methanol (95:5) to yield the title compound as colourless solid (257 mg).

1. concentrationthe mixture was concentrated under reduced pressure
2. additionTo the yellow solid was added water (30 ml)
3. extractionthe mixture was extracted with dichloromethane (3×30 ml)
4. customdried on sodium sulfate
5. concentrationconcentrated under reduced pressure
6. dissolutionThe residue was dissolved in ethanol (6 ml)
7. additiondichloromethane (1 ml) and an excess of an aqueous solution of sodium hydroxyde (2N) was added
8. additionThe reaction mixture was then diluted with dichloromethane (100 ml)
9. customThe phases were separated
10. extractionthe aqueous phase was extracted with dichloromethane (2×50 ml)
11. customThe combined organic fractions were dried on sodium sulfate
12. concentrationconcentrated under reduced pressure
13. customThe residue was purified by column chromatography (silica, 20 g)
14. washeluted with dichloromethane:methanol (95:5)