Dimethylformamide → 2-(1,3-Dioxolan-2-yl)-3-furaldehyde

Temperatur

-78 °C

2-(3-Bromo-2-furyl)-1,3-dioxolane (438 mg, 2.0 mmol) is dissolved in Et2O (5 mL) in an oven-dried flask, under nitrogen, cooled to −78° C., treated dropwise with tert-butyllithium (2.59 mL, 4.4 mmol) and stirred for 1 h. DMF (178 μL, 2.3 mmol) in Et2O (2 mL) is added dropwise, the mixture stirred for 4 h at −78° C., then treated with oxalic acid dihydrate (504 mg, 4.0 mmol) followed by water (2 mL). The cooling bath is removed and the mixture allowed to warm to rt over 1 h. The mixture is diluted with water (20 mL) and EtOAc (20 mL), the layers are separated and the aqueous layer extracted with EtOAc (1×20 mL). The organics are dried over Na2SO4 and concentrated to a yellow oil. The crude material is chromatographed over 12 g slurry-packed silica gel, eluting with 15% EtOAc/hexane. The appropriate fractions are combined and concentrated in vacuo to afford 228 mg (68%) of 2-(1,3-dioxolan-2-yl)-3-furaldehyde as a pale yellow oil. MS (EI) m/z: 168 (M+).

1. stirringthe mixture stirred for 4 h at −78° C.
2. customThe cooling bath is removed
3. temperatureto warm to rt over 1 h
4. additionThe mixture is diluted with water (20 mL) and EtOAc (20 mL)
5. customthe layers are separated
6. extractionthe aqueous layer extracted with EtOAc (1×20 mL)
7. dry with materialThe organics are dried over Na2SO4
8. concentrationconcentrated to a yellow oil
9. customThe crude material is chromatographed over 12 g slurry-packed silica gel
10. washeluting with 15% EtOAc/hexane
11. concentrationconcentrated in vacuo

ORD-Eintrag

ord-a31de2cd9c224a8b8c1344c5513eb6ae

Quelldatensatz

uspto-grants-2006_06

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07067515B2