Reaktion #460636

Reaktionsgleichung

sodium methoxide

methanol

3-benzylthio-7-fluoro-5-methylthio-1,2,4-triazolo[4,3-c]pyrimidine

2-benzylthio-7-fluoro-5-methylthio-1,2,4-triazolo[1,5-c]pyrimidine

diethyl maleate

→

title compound

Ausbeute 56.7%

2-Benzylthio-7-fluoro-5-methoxy-1,2,4-triazolo[1,5-c]pyrimidine

Ausbeute 56.7%

Lösungsmittel

Acetic acid

ethanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeto react for about 1 hour
2. 2
   Sonstigethe volatiles were removed by evaporation under reduced pressure
3. 3
   workup.DISSOLUTIONThe residue was dissolved in methylene chloride
4. 4
   Extraktionthe resulting solution was extracted with water
5. 5
   Trocknendried over magnesium sulfate
6. 6
   Einengenconcentrated by evaporation under reduced pressure
7. 7
   SonstigeThe residue was triturated with hexane
8. 8
   Filtrationfiltered
9. 9
   Sonstigedried

Vorschrift

A 25 percent solution of sodium methoxide in methanol (1.9 ml, 0.0085 mol) was added to a solution of 19.9 g (0.065 mol) of 3-benzylthio-7-fluoro-5-methylthio-1,2,4-triazolo[4,3-c]pyrimidine containing a small amount of 2-benzylthio-7-fluoro-5-methylthio-1,2,4-triazolo[1,5-c]pyrimidine and 11.2 g (0.065 mol) of diethyl maleate in 250 ml of ethanol at ambient temperature with stirring and allowed to react for about 1 hour. Acetic acid (4 ml) was then added and the volatiles were removed by evaporation under reduced pressure. The residue was dissolved in methylene chloride and the resulting solution was extracted with water, dried over magnesium sulfate, and concentrated by evaporation under reduced pressure. The residue was triturated with hexane, filtered, and dried to obtain 10.7 g of the title compound as a white powder melting at 121°-122° C. The nmr and uv spectra were consistent with the assigned structure.

Quelle