反应详情

温度

0 °C

Under ice-cooling, 9-fluorenemethanol (99%, 0.694 g, 3.5 mmol), bromoacetic acid (99%, 0.406 g, 2.9 mmol), DPTS (0.130 g, 0.44 mmol) and DCC (99%, 0.729 g, 3.5 mmol) were combined in dichloromethane (9 mL), stirred at 0° C. for 1 h, and the precipitate of dicyclohexylurea was filtered off from the cold mixture. The filtrate was diluted with cold ethyl acetate (30 mL), washed twice with cold 5% aqueous solution of NaH2PO4 (60 mL, acidified with H3PO4 to pH=3), freed of water droplets, and the solvents were distilled off in vacuo. The residue was extracted with cold pentane to remove the excess of DCC, and purified by flash chromatography (silica-gel, hexane-CHCl3, 5:1 to 1:1) followed by crystallization from cold hexane. Yield of 8: 0.795 g (87%). The purity was confirmed by TLC (SiO2, heptane-ethyl acetate, 9:1).

1. temperatureUnder ice-cooling
2. filtrationthe precipitate of dicyclohexylurea was filtered off from the cold mixture
3. additionThe filtrate was diluted with cold ethyl acetate (30 mL)
4. washwashed twice with cold 5% aqueous solution of NaH2PO4 (60 mL, acidified with H3PO4 to pH=3)
5. distillationthe solvents were distilled off in vacuo
6. extractionThe residue was extracted with cold pentane
7. customto remove the excess of DCC
8. custompurified by flash chromatography (silica-gel, hexane-CHCl3, 5:1 to 1:1)
9. customfollowed by crystallization from cold hexane