反应 #4976
ord-524d531152204c2e8e6ceed8643f94a1
反应方程式
反应物
反应条件
后处理
- 1workup.STIRRINGslowly with stirring
- 2workup.STIRRINGto stir as above for 72 hours
- 3过滤After this time the reaction mixture is filtered through a pad of diatomaceous earth
- 4洗涤The precipitate is washed with chloroform (5×10 mL)
- 5萃取the combined organic filtrates are extracted with 1M aqueous HCl (1×75 mL), saturated aqueous sodium bicarbonate solution (1×75 mL), 1M sodium thiosulfate (1×75 mL), and water (1×75 mL)
- 6干燥The organic layer is dried over anhydrous sodium sulfate
- 7过滤filtered
- 8其他evaporated under reduced pressure
- 9干燥dried in vacuo to an orange-brown powder (440 mg)
实验过程
A mixture of 7-hydroxy-2-octadecyl-3H-phenoxazine-3-one ("octadecylresorufin) (220 mg, 0.47 mmole), powdered, activated 4Å molecular sieves (0.5 g), sym-collidine (125 μL, 0.95 mmole), and silver carbonate (155 mg, 0.56 mmole) in dry dichloromethane (20 mL) is allowed to stir at room temperature, under an atmosphere of dry nitrogen gas, in the dark for 1 hour. To this mixture is added 1-bromo-2,3,4,6-tetra-O-acetyl-α-D-galactopyranoside (389 mg, 0.95 mmole), slowly with stirring, and the resulting heterogenous solution allowed to stir as above for 72 hours. After this time the reaction mixture is filtered through a pad of diatomaceous earth. The precipitate is washed with chloroform (5×10 mL) and the combined organic filtrates are extracted with 1M aqueous HCl (1×75 mL), saturated aqueous sodium bicarbonate solution (1×75 mL), 1M sodium thiosulfate (1×75 mL), and water (1×75 mL). The organic layer is dried over anhydrous sodium sulfate, filtered, evaporated under reduced pressure, and dried in vacuo to an orange-brown powder (440 mg). An analytical sample of the title compound can be isolated by preparative t.l.c. (20×20 cm SiO2 plate; eluent=9:1 chloroform:ethylacetate) with the bright-orange product eluting at the highest Rf (0.44), (50 mg from 200 mg applied).