반응 #71024

반응 방정식

N2

n-BuLi

NH4Cl

2-furan-2-yl-2-methyl-[1,3]dioxolane

DMF

→

5-(2-methyl-[1,3]dioxolan-2-yl)-furan-2-carbaldehyde

수율 166.7%

용매

hexane

THF

THF

반응 조건

후처리

1. 1
   workup.ADDITIONwas added dropwise
2. 2
   추출the mixture was extracted with EA (2×50 mL)
3. 3
   건조extracts were dried over MgSO4
4. 4
   여과filtered
5. 5
   기타the solvent was removed under reduced pressure

실험 절차

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.

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