反应详情

A sample of 2.60 g (20.6 mmol) of commercially available (Aldrich) (S)-(−)-1,2,4-butanetriol 5, benzaldehyde (3.47 mL, 29 mmol), and trimethyl orthoformate (3.74 mL, 29 mmol) was dissolved in 80 mL of CH2Cl2, and 1 mL of CF3CO2H was added. After the reaction mixture was stirred for 24 hours at room temperature, the reaction was quenched by the addition of NaOMe (20 mg), diluted with 100 mL of ether, and filtered. After the filtrate was concentrated under reduced pressure, the residue was purified by column chromatography on silica gel, eluting with petroleum ether (PE)-EtOAc (5:1 to ˜1:1) to afford 3.6 g (90%) of the product as a colorless oil. 1H NMR (300 MHz, CDCl3) δ7.52-7.33 (m, 5H), 5.51 (s, 1H), 4.29 (dd, J=4.1, 10.7 Hz, 1H), 3.95 (m, 2H), 3.60 (m, 2H), 2.85 (s, 1H, OH), 1.85 (m, 2H). 13C-NMR (CDCl3, 75 MHz): δ139.10, 129.58, 128.90, 126.85, 101.96, 78.35, 67.36, 66.29, 27.69.

1. customthe reaction was quenched by the addition of NaOMe (20 mg)
2. additiondiluted with 100 mL of ether
3. filtrationfiltered
4. concentrationAfter the filtrate was concentrated under reduced pressure
5. customthe residue was purified by column chromatography on silica gel
6. washeluting with petroleum ether (PE)-EtOAc (5:1 to ˜1:1)