反应详情

The resultant compound of Example 82(b) (1.45 g, 4.95 mmol), in 10 ml THF was added dropwise to the cooled suspension of sodium hydride (60% dispersion in oil, 0.5 g, 11.2 mmol) in 4 ml THF (0°-5° C.). The suspension was stirred for 20 mins at 0°-5° C. and then warmed up to room temperature and stirred for additional 1 h. Solution of D-2-bromohexanoic acid in 6 ml THF was added dropwise to the cooled suspension (0°-5° C.) at N2 atmosphere. It was then allowed to warm up to room temperature and stirred overnight. Quenched with cold H2O and extracted with ethylacetate to remove undesired starting material. It was acidified with 1M sodium hydrogen sulfate and extracted with chloroform. After filtration and evaporation, the crude product was purified on silica gel, eluted with CH2Cl2 : CH3OH: AcOH (19.4=0.3:0.3) to obtain 0.79 g of desired acid (43% yield).

1. stirringstirred for additional 1 h
2. temperatureto warm up to room temperature
3. stirringstirred overnight
4. customQuenched with cold H2O
5. extractionextracted with ethylacetate
6. customto remove undesired
7. extractionextracted with chloroform
8. filtrationAfter filtration and evaporation
9. customthe crude product was purified on silica gel
10. washeluted with CH2Cl2