反应详情

A solution of impure 2,2-dimethyl-1-[2-phenoxy-5-(2-trimethylsilanyl-ethoxymethyl)-5H-pyrrolo[2,3-b]pyrazin-7-yl]-propan-1-one, prepared according to general procedures as described in these Examples, (0.032 g, “0.075 mmol”) in 1 mL of dichloromethane and 1 mL of trifluoroacetic acid was stirred for 13 h, then concentrated to a yellow-green oil, which was partitioned between 5 mL of a sat. aq. NaHCO3 solution and 5 mL of dichloromethane. The aqueous layer was extracted with 5 mL of dichloromethane, and the combined organic layers were dried over MgSO4, filtered and concentrated to a pale yellow oil. The oil was dissolved in 1 mL of ethanol and treated with sodium acetate trihydrate (0.103 g, 0.756 mmol). The mixture was stirred for 2 h, then concentrated. The residue was partitioned between 5 mL of water and 5 mL of dichloromethane. The aqueous layer was extracted with 5 mL of dichloromethane, and the combined organic layers were dried over MgSO4, filtered and concentrated to a pale yellow oil. The oil was again dissolved in 1 mL of ethanol and treated with sodium acetate trihydrate (0.101 g, 0.745 mmol). The mixture was stirred for 4 h, then concentrated. The residue was partitioned between 5 mL of water and 5 mL of dichloromethane. The aqueous layer was extracted with 5 mL of dichloromethane, and the combined organic layers were dried over MgSO4, filtered and concentrated to an off-white solid. Column chromatography (0→33% EtOAc/hexanes) afforded 0.014 g (65% from impure; 40% 2-step) of 2,2-dimethyl-1-(2-phenoxy-5H-pyrrolo[2,3-b]pyrazin-7-yl)-propan-1-one as an off-white solid.

1. concentrationconcentrated to a yellow-green oil, which
2. customwas partitioned between 5 mL of a sat. aq. NaHCO3 solution and 5 mL of dichloromethane
3. extractionThe aqueous layer was extracted with 5 mL of dichloromethane
4. dry with materialthe combined organic layers were dried over MgSO4
5. filtrationfiltered
6. concentrationconcentrated to a pale yellow oil
7. dissolutionThe oil was dissolved in 1 mL of ethanol
8. concentrationconcentrated
9. customThe residue was partitioned between 5 mL of water and 5 mL of dichloromethane
10. extractionThe aqueous layer was extracted with 5 mL of dichloromethane
11. dry with materialthe combined organic layers were dried over MgSO4
12. filtrationfiltered
13. concentrationconcentrated to a pale yellow oil
14. dissolutionThe oil was again dissolved in 1 mL of ethanol
15. stirringThe mixture was stirred for 4 h
16. concentrationconcentrated
17. customThe residue was partitioned between 5 mL of water and 5 mL of dichloromethane
18. extractionThe aqueous layer was extracted with 5 mL of dichloromethane
19. dry with materialthe combined organic layers were dried over MgSO4
20. filtrationfiltered
21. concentrationconcentrated to an off-white solid