Reaktion #1149920

Reaktionsgleichung

2-{[5-amino-4-(1,3-benzodioxol-5-yl)-1-methyl-1H-pyrazol-3-yl]oxy}ethyl acetate

5-isopropyl-2-pyridinesulfonyl chloride

citric acid

→

title compound

Ausbeute 2.5%

N-[4-(1,3-benzodioxol-5-yl)-3-(2-hydroxyethoxy)-1-methyl-1H-pyrazol-5-yl]-5-isopropyl-2-pyridinesulfonamide

Ausbeute 2.5%

Lösungsmittel

pyridine

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.WAITAfter being left
2. 2
   Temperaturto reflux overnight
3. 3
   Extraktionextracted with ethyl acetate (2×50 ml)
4. 4
   WaschenThe organic fractions were washed with brine (50 ml)
5. 5
   Trocknenby drying over magnesium sulfate
6. 6
   Filtrationfiltering
7. 7
   Einengenconcentration under reduced pressure
8. 8
   workup.ADDITIONTo a solution of the residue in ethanol (50 ml) was added sodium hydroxide solution (5 ml of 2M)
9. 9
   Einengenbefore being concentrated to approximately 5 ml under reduced pressure
10. 10
    Sonstigepartitioned between ethyl acetate (2×100 ml) and saturated citric acid solution (100 ml)
11. 11
    WaschenWashing of the organic fractions with brine (100 ml)
12. 12
    Trocknendrying over magnesium sulfate
13. 13
    Filtrationfiltering
14. 14
    Einengenconcentration under reduced pressure
15. 15
    Sonstigeafforded a brown residue
16. 16
    SonstigePurification by column chromatography on silica gel (5 g)
17. 17
    Wascheneluting in an isocratic fashion with ethyl acetate:hexane (2:1)

Vorschrift

To a solution of 2-{[5-amino-4-(1,3-benzodioxol-5-yl)-1-methyl-1H-pyrazol-3-yl]oxy}ethyl acetate (Preparation 33) (500 mg) in anhydrous pyridine (5 ml) at room temperature and under an atmosphere of nitrogen was added 4-dimethylaminopyridine (191 mg) and 5-isopropyl-2-pyridinesulfonyl chloride (1.72 g). After being left to reflux overnight, the reaction mixture was poured onto saturated citric acid solution (50 ml) and extracted with ethyl acetate (2×50 ml). The organic fractions were washed with brine (50 ml), followed by drying over magnesium sulfate, filtering and concentration under reduced pressure. To a solution of the residue in ethanol (50 ml) was added sodium hydroxide solution (5 ml of 2M). The mixture was stirred overnight before being concentrated to approximately 5 ml under reduced pressure and partitioned between ethyl acetate (2×100 ml) and saturated citric acid solution (100 ml). Washing of the organic fractions with brine (100 ml), drying over magnesium sulfate, filtering and concentration under reduced pressure afforded a brown residue. Purification by column chromatography on silica gel (5 g), eluting in an isocratic fashion with ethyl acetate:hexane (2:1) afforded the title compound as a gum (18 mg).

Quelle