Tetrahydrofuran → 5-Methyl-4-triisopropylsilanyloxymethyl-furan-2-carbaldehyde
Reaktionsgleichung
[CH:1]([Si:4]([CH:16]([CH3:18])[CH3:17])([CH:13]([CH3:15])[CH3:14])[O:5][CH2:6][C:7]1[CH:11]=[CH:10][O:9][C:8]=1[CH3:12])([CH3:3])[CH3:2].C([Li])(CC)C.[Cl-].[NH4+].[O:26]1CCC[CH2:27]1>>[CH3:12][C:8]1[O:9][C:10]([CH:27]=[O:26])=[CH:11][C:7]=1[CH2:6][O:5][Si:4]([CH:1]([CH3:3])[CH3:2])([CH:13]([CH3:15])[CH3:14])[CH:16]([CH3:18])[CH3:17]Komponenten
5
Versuchsvorschrift
A solution of triisopropyl-(2-methyl-furan-3-ylmethoxy)-silane (14) (10 g) in tetrahydrofuran (250 mL) was cooled to −78° C. with stirring, and then sec-butyllithium (1.3 M in cyclohexane; 37.25 mL) was added drop-wise over 10 mins. After stirring for 45 mins at −78° C., the cooling bath was removed for a period of 15 mins then re-introduced. A solution of N,N-dimethylformamide (14.4 mL) in tetrahydrofuran (25 mL) was added drop-wise and the resulting reaction mixture was stirred at −78° C. for a further 2 hours. The reaction mixture was allowed to warm to room temperature and then poured into saturated ammonium chloride solution (150 mL). This mixture was extracted with diethyl ether (2×350 mL), and the combined organic extracts were washed with water (500 mL) and brine (500 mL), dried, and concentrated in vacuo to give compound 33 as an amber coloured oil. LC/MS System A: Rt=4.86 mins.