反应详情

To a stirred solution of 1,3-dipropyl-7-pyrrolidin-1-ylmethyl-3,7-dihydro-purine-2,6-dione (Example 48) (522 mg, 1.63 mmol) in THF (50 ml) at −78° C. was added n-BuLi (1.55 M in hexanes, 1.2 eq, 1.3 ml). The color of the resulting yellow mixture deepened to orange-red and was stirred at this temperature for 0.5 h. A solution of 8-oxa-bicyclo[3.2.1]oct-6-en-3-one (1.1 eq, 222 mg, 1.79 mmol) in THF (4 ml) was added via syringe over a period of 20 minutes. The mixture was held at −78° C. for 2 h and allowed to reach ambient temperature overnight (12 h). The reaction mixture was partitioned between saturated aqeuous NH4Cl (20 ml) and EtOAc (20 ml) and the aqueous phase was extracted with EtOAc (20 ml). The combined organic extracts were washed with saturated aqeuous NaCl (20 ml), dried (MgSO4), filtered and concentrated in vacuo. The resulting orange oil was purified by chromatography on silica using 5% MeOH in CH2Cl2 as eluent to give a clear oil that solidified upon standing (50 mg, 8%).

1. waitThe mixture was held at −78° C. for 2 h
2. waitto reach ambient temperature overnight
3. custom(12 h)
4. customThe reaction mixture was partitioned between saturated aqeuous NH4Cl (20 ml) and EtOAc (20 ml)
5. extractionthe aqueous phase was extracted with EtOAc (20 ml)
6. washThe combined organic extracts were washed with saturated aqeuous NaCl (20 ml)
7. dry with materialdried (MgSO4)
8. filtrationfiltered
9. concentrationconcentrated in vacuo
10. customThe resulting orange oil was purified by chromatography on silica using 5% MeOH in CH2Cl2 as eluent
11. customto give a clear oil that