Ethyl formate → HCID 58013985, Verbindung

Temperatur

-78 °C

In an argon atmosphere, a 2.67 mol/L n-butyl lithium-hexane solution (14.0 mL) was added dropwise to a solution of the compound of Example 91 (12.4 g) in tetrahydrofuran (200 mL) at −78° C. The mixture was stirred at −78° C. for 30 min. Subsequently, the mixture was added dropwise to a solution of ethyl formate (9.06 mL) in tetrahydrofuran (100 mL) at −78° C. The mixture was then allowed to gradually warm to room temperature. A saturated aqueous ammonium chloride solution was added and the mixture was extracted with ethyl acetate (400 mL). The organic layer was washed sequentially with water and saturated brine and dried over anhydrous sodium sulfate. The extract was concentrated and the residue was purified by silica gel column chromatography (hexane:ethyl acetate=15:1) to give yellow crystals. This product was dissolved in methanol (200 mL). While the solution was kept at 0° C., sodium borohydride (1.56 g) was added and the mixture was stirred at 0° C. for 1 hour. Subsequently, a saturated aqueous ammonium chloride solution was added. The mixture was concentrated and extracted with ethyl acetate (700 mL).

1. temperatureto gradually warm to room temperature
2. extractionthe mixture was extracted with ethyl acetate (400 mL)
3. washThe organic layer was washed sequentially with water and saturated brine
4. dry with materialdried over anhydrous sodium sulfate
5. concentrationThe extract was concentrated
6. customthe residue was purified by silica gel column chromatography (hexane:ethyl acetate=15:1)
7. customto give yellow crystals
8. customwas kept at 0° C.
9. stirringthe mixture was stirred at 0° C. for 1 hour
10. concentrationThe mixture was concentrated
11. extractionextracted with ethyl acetate (700 mL)

ORD-Eintrag

ord-ab6ab0191c294c868931362051a90419

Quelldatensatz

uspto-grants-2010_07

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07763617B2