Reaktion #68097

Reaktionsgleichung

sodium hydrogen carbonate

1-(2-(4-aminopiperidin-1-yl)ethyl)-7-methoxyquinoxalin-2(1H)-one

3-oxo-3,4-dihydro-2H-1,4-benzooxazine-6-carbaldehyde

sodium cyanoborohydride

→

6-(((1-(2-(7-methoxy-2-oxoquinoxaline-1-(2H)-yl)ethyl)piperidin-4-yl)amino)methyl)-2H-1,4-benzooxazine-3(4H)-one

Ausbeute 19.2%

Lösungsmittel

chloroform

chloroform

ethyl acetate

acetic acid

methanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONwere added at room temperature
2. 2
   Sonstigethe organic layer was separated
3. 3
   Extraktionthe aqueous layer was extracted with chloroform
4. 4
   Waschenwashed sequentially with water and aqueous saturated sodium chloride solution
5. 5
   Trocknendried over anhydrous magnesium sulfate
6. 6
   Sonstigethe solvent was removed under reduced pressure
7. 7
   SonstigeThe residue thus obtained
8. 8
   Sonstigewas purified by silica gel column chromatography [eluent; chloroform:methanol=5:1], diethyl ether
9. 9
   workup.ADDITIONwas added to the foam
10. 10
    Sonstigethus obtained
11. 11
    Filtrationthe resulting solid was filtered
12. 12
    Sonstigeto afford a yellow solid
13. 13
    Temperaturafter heating
14. 14
    Filtrationthe resulting solid was filtered

Vorschrift

To 3.0 mL of a methanol solution containing 0.20 g of 1-(2-(4-aminopiperidin-1-yl)ethyl)-7-methoxyquinoxalin-2(1H)-one, 0.12 g of 3-oxo-3,4-dihydro-2H-1,4-benzooxazine-6-carbaldehyde, 38 μL of acetic acid and 83 mg of sodium cyanoborohydride were added at room temperature and stirred at the same temperature for 6.5 hours. To the reaction mixture, chloroform and aqueous saturated sodium hydrogen carbonate solution were added to be adjusted to pH 10.2, the organic layer was separated, and the aqueous layer was extracted with chloroform. The organic layer and extracts were combined, washed sequentially with water and aqueous saturated sodium chloride solution, dried over anhydrous magnesium sulfate, and the solvent was removed under reduced pressure. The residue thus obtained was purified by silica gel column chromatography [eluent; chloroform:methanol=5:1], diethyl ether was added to the foam thus obtained, and the resulting solid was filtered to afford a yellow solid. To this solid, ethyl acetate and chloroform were added, the mixture was cooled to the room temperature after heating, and the resulting solid was filtered to give 59 mg of 6-(((1-(2-(7-methoxy-2-oxoquinoxaline-1-(2H)-yl)ethyl)piperidin-4-yl)amino)methyl)-2H-1,4-benzooxazine-3(4H)-one a pale yellow solid.

Quelle