反应详情

温度

-20 °C

2,3,4,6-Tetra-O-acetyl-α-D-galactopyranosyl 2,2,2-trichloroacetimidate 1 (9.85 g, 20 mmol) and 4-hydroxybenzaldehyde (3.66 g, 30 mmol) were dissolved in CH2Cl2 (100 mL) and then the reaction mixture was cooled to −20° C. Boron trifluoride diethyl etherate (46%, 16 mL, 60 mmol) was added dropwise at this temperature. The reaction mixture was stirred at −20° C. for 4 h and was monitored by TLC. Saturated NaHCO3 aqueous solution (150 mL) was added to the mixture. The aqueous layer was separated and extracted with CH2Cl2 (2×150 mL). The organic layers were combined, dried over MgSO4 and concentrated. Purification by silica gel column chromatography yielded 2 (3.8 g, 42%) as a white solid.

1. customThe aqueous layer was separated
2. extractionextracted with CH2Cl2 (2×150 mL)
3. dry with materialdried over MgSO4
4. concentrationconcentrated
5. customPurification by silica gel column chromatography