Trifluoroacetic anhydride → 2-(Methoxycarbonyl)-3-methylpyrazine 1-oxide
Reaktionsgleichung
[CH3:1][C:2]1[C:3]([C:8]([O:10][CH3:11])=[O:9])=[N:4][CH:5]=[CH:6][N:7]=1.C(N)(N)=[O:13].OO.FC(F)(F)C(OC(=O)C(F)(F)F)=O.COC(C1C(C)=[N+]([O-])C=CN=1)=O>C(Cl)Cl>[CH3:11][O:10][C:8]([C:3]1[C:2]([CH3:1])=[N:7][CH:6]=[CH:5][N+:4]=1[O-:13])=[O:9]Komponenten
Edukt 4
Produkt 1
Reagenzien, Katalysatoren, Lösungsmittel 1
Reaktionsbedingungen
- Temperatur
- 0 °C
Versuchsvorschrift
To a solution of methyl 3-methylpyrazine-2-carboxylate (9.1 g, 59.8 mmol) in DCM (100 mL) at 0° C., was added urea hydrogen peroxide adduct, 97% (7.81 g, 83 mmol) and trifluoroacetic acid anhydride (10.8 ml, 78 mmol) dropwise. The resulting mixture was stirred at 0° C. for 1 h, and at room temperature for 18 h. The reaction was diluted with DCM and quenched with saturated Na2SO3 solution; the aqueous layer was back-extracted with DCM. The combined organic extracts were dried (MgSO4), filtered and concentrated in vacuo. The crude mixture was purified with ISCO (20% to 80% EtOAc/Hexanes) to afford a mixture of products: 2-(methoxycarbonyl)-3-methylpyrazine 1-oxide (5.2 g, 51.7% yield) and 3-(methoxycarbonyl)-2-methylpyrazine 1-oxide. The mixture was taken to next step without further purification.
Aufarbeitung
- waitat room temperature for 18 h
- customquenched with saturated Na2SO3 solution
- extractionthe aqueous layer was back-extracted with DCM
- dry with materialThe combined organic extracts were dried (MgSO4)
- filtrationfiltered
- concentrationconcentrated in vacuo
- customThe crude mixture was purified with ISCO (20% to 80% EtOAc/Hexanes)
- customto afford
- additiona mixture of products
Quellen und Nachweise
- ORD-Eintrag
- ord-ac510f0b48b345f09c0b4d7c7e7391db
- Quelldatensatz
- uspto-grants-2016_04
- Patentnummer
- US09309263B2
Notizen zur Reaktion
Wird geladen…