Reaktion #467916

Reaktionsgleichung

N-(3,5-dichloropyridin-4-yl)-3-hydroxy-4-methoxybenzamide

potassium carbonate

3,4-epoxytetrahydrofuran

→

title compound

Ausbeute 27.1%

N-(3,5-Dichloropyridin-4-yl)-3-(4-hydroxytetrahydrofuran-3-yloxy)-4-methoxybenzamide

Ausbeute 27.1%

Lösungsmittel

dimethylformamide

Reaktionsbedingungen

Aufarbeitung

1. 1
   EinengenThe mixture is concentrated
2. 2
   workup.ADDITION50 ml of water are added
3. 3
   Extraktionextracted with 3×50 ml of ethyl acetate
4. 4
   WaschenThe combined organic phases are washed with saturated sodium chloride solution
5. 5
   Trocknendried over magnesium sulfate
6. 6
   Einengenconcentrated
7. 7
   Sonstigethe residue is chromatographed on silica gel [toluene/ethyl acetate=1:2]
8. 8
   EinengenThe product-containing fractions are concentrated
9. 9
   Sonstigethe residue is crystallized from diethyl ether

Vorschrift

400 mg (1.2 mmol) of N-(3,5-dichloropyridin-4-yl)-3-hydroxy-4-methoxybenzamide (starting compound A16) and 540 mg (3.85 mmol) of potassium carbonate are stirred under a nitrogen atmosphere at RT for 1 h in 5 ml of dimethylformamide. The mixture is heated to 120° C. and 115 mg (1.3 mmol) of 3,4-epoxytetrahydrofuran are added to the reaction mixture 4×at an interval of 6 h in each case. The mixture is concentrated, 50 ml of water are added, it is acidified with 2 N HCl and extracted with 3×50 ml of ethyl acetate. The combined organic phases are washed with saturated sodium chloride solution, dried over magnesium sulfate, concentrated and the residue is chromatographed on silica gel [toluene/ethyl acetate=1:2]. The product-containing fractions are concentrated and the residue is crystallized from diethyl ether. 130 mg of the title compound of m.p. 183-185° C. are obtained.

Quelle