Reaktion #435040

Reaktionsgleichung

N-Chlorosuccinimide

2-ethylpyrazolo[1,5-a]pyridine

sodium iodide

→

title compound

Ausbeute 99.1%

2-Ethyl-3-iodopyrazolo[1,5-a]pyridine

Ausbeute 99.1%

Lösungsmittel

water

ethyl acetate

ethyl acetate

ethyl acetate

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturwhile cooling with ice
2. 2
   workup.ADDITIONwere added to the reaction mixture and extraction
3. 3
   ExtraktionThe organic extract
4. 4
   Waschenwas washed twice with 10% aqueous sodium thiosulfate
5. 5
   Einengenconcentrated
6. 6
   workup.ADDITIONHexane was added to the residue
7. 7
   Temperaturthe mixture was heated to dissolution
8. 8
   Filtrationthe resulting solution was filtered
9. 9
   Sonstigeto remove insoluble residue
10. 10
    WaschenAfter then washing the hexane solution with water
11. 11
    Einengenthe hexane layer was concentrated
12. 12
    workup.DISSOLUTIONthe residue was dissolved in ethyl acetate
13. 13
    Sonstigethe solvent was evaporated

Vorschrift

N-Chlorosuccinimide (411 g, 3.08 mol) was gradually added to a mixture of 2-ethylpyrazolo[1,5-a]pyridine (360 g, 2.46 mol), ethyl acetate (3600 mL), water (1800 mL) and sodium iodide (480 g, 3.20 mol, 1.3 equivalents) over a period of 30 minutes while cooling with ice, and then the reaction mixture was stirred for 2 hours and 20 minutes at room temperature. After the reaction, water and ethyl acetate were added to the reaction mixture and extraction was performed with ethyl acetate. The organic extract was washed twice with 10% aqueous sodium thiosulfate, and then concentrated. Hexane was added to the residue, the mixture was heated to dissolution and the resulting solution was filtered to remove insoluble residue. After then washing the hexane solution with water, the hexane layer was concentrated, the residue was dissolved in ethyl acetate and the solvent was evaporated to afford 663 g of the title compound (98.9% yield).

Quelle