Methanol → HCID 57867359, Verbindung
Reaktionsgleichung
[C:1]([O:9][CH2:10][C@@H:11]1[C@@H:15]([O:16][C:17](=[O:24])[C:18]2[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=2)[C@:14]([F:26])([CH3:25])[CH:13]([OH:27])[O:12]1)(=[O:8])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[CH3:28]O>>[C:1]([O:9][CH2:10][C@@H:11]1[C@@H:15]([O:16][C:17](=[O:24])[C:18]2[CH:19]=[CH:20][CH:21]=[CH:22][CH:23]=2)[C@:14]([F:26])([CH3:25])[CH:13]([O:27][CH3:28])[O:12]1)(=[O:8])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1Komponenten
3
Reaktionsbedingungen
- Temperatur
- 80 °C
Versuchsvorschrift
To a stirred solution of ((2R,3R,4R)-3-benzoyloxy-4-fluoro-5-hydroxy-4-methyl-tetrahydrofuran-2-yl)methyl benzoate (about 60 g, 160 mmol) in methanol (about 300 ml), boron trifluoro etherate (about 60.02 ml, 481 mmol) was added at room temperature then reaction mixture was heated to about 80° C. for about 5 hours. After that the reaction was quenched with saturated sodium bicarbonate solution, methanol was removed under reduced pressure, extracted with ethyl acetate. The combined organic extracts were washed with water, brine and dried over sodium sulphate. The organic layer was removed under reduced pressure and the residue was purified by silica gel column chromatography using 8% ethyl acetate: hexane as eluent furnished title compound A (17 g), and 15% ethyl acetate eluded title compound B (18 g) as a colorless liquid. Yield: Combined yield: 56.2%; Intermediate A: 1H NMR (300 MHz, CDCl3) compound D: δ 8.01-7.93 (m, 4H), 7.56-7.48 (m, 6H), 5.53 (dd, 1H, J=24.3 Hz, 7.80 Hz), 4.97 (d, 1H, J=9.6 Hz), 4.58-4.53 (m, 2H), 4.41-4.38 (m, 1H), 3.30 (s, 3H), 1.44 (d, 3H, J=22.8); Mass: [M+Na]+: 413 (80%), [M-OCH3]+:357.19 (100%); IR cm−: 3439, 2961, 2939, 1728, 1602, 1452, 1270, 1117, 710.