Reaktion #63920

Reaktionsgleichung

sodium bicarbonate

3-methyl-6-[3-(amino)phenyl]-1,2,4-triazolo[4,3-b]pyridazine

diisopropylamine

4-chlorobutyryl chloride

→

white crystals

1-[3-(3-Methyl-1,2,4-triazolo[4,3-b]pyridazin-6-yl)phenyl]-2-pyrolidinone

Lösungsmittel

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Extraktionextracted with 150 ml portions of dichloromethane
2. 2
   SonstigeThe combined extracts were dried
3. 3
   Einengenconcentrated in vacuo
4. 4
   workup.DISSOLUTIONThe residue was dissolved in 200 ml of dimethylformamide
5. 5
   workup.ADDITION2.0 g of potassium carbonate was added
6. 6
   workup.ADDITIONpoured onto 200 ml of water
7. 7
   Extraktionextracted with 150 ml portions of dichloromethane
8. 8
   SonstigeThe combined extracts were dried
9. 9
   Einengenconcentrated in vacuo
10. 10
    Sonstigechromatographed on 300 g of silica gel with dichloromethane-methanol (97:3)
11. 11
    workup.ADDITIONThe fractions containing the desired product
12. 12
    Einengenconcentrated in vacuo
13. 13
    Sonstigethe solid recrystallized from dichloromethane-hexane

Vorschrift

To a solution of 2 g of 3-methyl-6-[3-(amino)phenyl]-1,2,4-triazolo[4,3-b]pyridazine in 400 ml of dichloromethane was added 1.7 ml of diisopropylamine and 1 ml of 4-chlorobutyryl chloride. This solution was stirred for 12 hours, then poured onto 200 ml of saturated aqueous sodium bicarbonate and extracted with 150 ml portions of dichloromethane. The combined extracts were dried and concentrated in vacuo. The residue was dissolved in 200 ml of dimethylformamide and 2.0 g of potassium carbonate was added. This solution was heated to 80° C. for 12 hours, then poured onto 200 ml of water and extracted with 150 ml portions of dichloromethane. The combined extracts were dried, concentrated in vacuo and chromatographed on 300 g of silica gel with dichloromethane-methanol (97:3). The fractions containing the desired product were combined, concentrated in vacuo and the solid recrystallized from dichloromethane-hexane to give 1.67 g of white crystals, mp 235°-237° C.

Quelle