Nitrogen → 5-(2-Methyl-[1,3]dioxolan-2-yl)furan-2-carbaldehyde

Temperatur

-78 °C

In a flame dried round-bottomed flask equipped with a magnetic stir bar and under inert atmosphere (N2), to a solution of n-BuLi (14.6 mL of a 1.6M solution in hexane, 23.35 mmol) in THF (21 mL) at −78° C. was added dropwise a solution of 2-furan-2-yl-2-methyl-[1,3]dioxolane (3.00 g, 19.46 mmol) in THF (6.0 mL). The reaction mixture was then stirred for 1 h at −78° C. before DMF (4.52 mL, 58.38 mmol) was added dropwise. The reaction mixture was stirred for 1 h at −78° C. Sat. aq. NH4Cl (50 mL) was added and the mixture was extracted with EA (2×50 mL). The combined org. extracts were dried over MgSO4, filtered, and the solvent was removed under reduced pressure to give 5.91 g of crude 5-(2-methyl-[1,3]dioxolan-2-yl)-furan-2-carbaldehyde as an orange oil. LC-MS-conditions 02: tR=0.75 min; [M+H]+=183.23. The crude material was dissolved, under inert atmosphere (N2) in MeOH (59.0 mL) and treated at 0° C., portionwise, over 20 min, with NaBH4 (1.53 g, 38.92 mmol in five equal portions). The reaction mixture was stirred for 45 min at rt. The reaction mixture was poured on water (80 mL) and the aq. layer was extracted with EA (2×60 mL). The combined org. extracts were dried over MgSO4, filtered, and the solvents were removed under reduced pressure. Purification of the residue by FC (50:50 hept-EA) gave the title compound: TLC:rf (50:50 hept-EA)=0.27. LC-MS-conditions 02: tR=0.65 min; [M+H]+=185.28.

1. additionwas added dropwise
2. extractionthe mixture was extracted with EA (2×50 mL)
3. dry with materialextracts were dried over MgSO4
4. filtrationfiltered
5. customthe solvent was removed under reduced pressure

ORD-Eintrag

ord-298d134c2e8c401796d9129a5ca7a7d2

Quelldatensatz

uspto-grants-2013_09

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08536209B2