反应详情

In a flame dried round-bottomed flask equipped with a magnetic stir bar and under inert atmosphere (N2), a solution of 5-(2-methyl-[1,3]dioxolan-2-yl)-pentanoic acid methyl ester (5.43 g, 26.85 mmol) in a mixture of THF (70 mL) and water (70 mL) was treated at rt with lithium hydroxide monohydrate (1.45 g, 34.55 mmol) and the mixture was stirred for 3 h at rt. The THF was removed under reduced pressure and the aqueous phase was washed with EA, concentrated under reduced pressure and poured in cold sat. aq. NH4Cl. The pH was adjusted to 4-5 using 1N HCl and the aqueous phase was extracted with EA (3×). The combined org. extracts were dried over Na2SO4, filtered, and the solvent was removed under reduced pressure. Purification of the residue by FC (20:1→1:2 hept-EA) gave the title compound as a white solid. LC-MS-conditions 02: tR=0.68 min [M+H]+=189.52.

1. customThe THF was removed under reduced pressure
2. washthe aqueous phase was washed with EA
3. concentrationconcentrated under reduced pressure
4. additionpoured in cold sat. aq. NH4Cl
5. extractionthe aqueous phase was extracted with EA (3×)
6. dry with materialextracts were dried over Na2SO4
7. filtrationfiltered
8. customthe solvent was removed under reduced pressure
9. customPurification of the residue by FC (20:1→1:2 hept-EA)