反应详情

温度

-78 °C

Step 1 8-Bromo-1-(3-((tert-butyldimethylsilyl)oxy)propyl)-7-(4-chlorobenzyl)-3-methyl-1H-purine-2,6(3H,7H)-dione (0.25 g, 0.46 mmol, intermediate 77) was dissolved in THF (5 mL) and cooled to −78° C. To the clear solution was added 2.5 M n-butyllithium in hexanes (0.20 mL, 0.51 mmol) dropwise. The reaction was stirred in the cold for 5 min and acetaldehyde (0.13 mL, 2.31 mmol) was added. The reaction was warmed to room temperature and stirred for 1 h. The reaction was diluted with water (100 mL) and extracted with ethyl acetate (3×75 mL). The combined extracts were dried with magnesium sulfate, filtered and the solvent was removed under reduced pressure to leave a golden oil. The oil was purified using two 1000 microns preparative TLC plates eluted with 50% ethyl acetate/hexanes. Target band was extracted with ethyl acetate and the solvent was removed under reduced pressure to give 1-(3-((tert-butyldimethysilyl)oxy)propyl)-7-(4-chlorobenzyl)-8-(1-hydroxyethyl)-3-methyl-1H-purine-2,6(3H,7H)-dione (0.052 g, 30% yield) as a clear oil. LCMS retention time=4.490 min and 97% purity, LCMS MH+ 507.

1. temperatureThe reaction was warmed to room temperature
2. stirringstirred for 1 h
3. extractionextracted with ethyl acetate (3×75 mL)
4. dry with materialThe combined extracts were dried with magnesium sulfate
5. filtrationfiltered
6. customthe solvent was removed under reduced pressure
7. customto leave a golden oil
8. customThe oil was purified
9. washeluted with 50% ethyl acetate/hexanes
10. extractionTarget band was extracted with ethyl acetate
11. customthe solvent was removed under reduced pressure