反应详情

To a solution of 1,1-dimethylethyl (4R)-4-({[(1,1-dimethylethyl)oxy]carbonyl}amino)-5-[4-(8-methylimidazo[1,2-a]pyridin-2-yl)phenyl]pentanoate (1.35 g, 2.82 mmol) in CH2Cl2 (14 mL) was added trifluoroacetic acid (10 mL) followed by triethylsilane (2.5 equiv, 7.04 mmol). The reaction was stirred for 45 minutes at room temperature and then concentrated in vacuo. DMF (35 mL) was added to the residue followed by diisopropylamine (14.7 mL, 84.51 mmol) under nitrogen. The reaction was stirred for 5 minutes and pentafluorophenyl 3-chloro-4-[(1-methylethyl)oxy]benzoate (1.1 equiv, 3.10 mmol) was added. The reaction was stirred for 45 minutes and then concentrated in vacuo. Ethyl acetate (50 mL) was added to the residue and it was washed with H2O (30 mL). The aqueous layer was extracted with EtOAc (20 mL) and the combined organic layers were dried over MgSO4 and concentrated in vacuo. Purification by silica gel chromatography (Analogix IF280, 25-100% EtOAc/hexanes) provided the title compound as a white foamy solid (61%). ESMS [M+H]+=520.2.

1. concentrationconcentrated in vacuo
2. additionDMF (35 mL) was added to the residue
3. stirringThe reaction was stirred for 5 minutes
4. stirringThe reaction was stirred for 45 minutes
5. concentrationconcentrated in vacuo
6. additionEthyl acetate (50 mL) was added to the residue and it
7. washwas washed with H2O (30 mL)
8. extractionThe aqueous layer was extracted with EtOAc (20 mL)
9. dry with materialthe combined organic layers were dried over MgSO4
10. concentrationconcentrated in vacuo
11. customPurification by silica gel chromatography (Analogix IF280, 25-100% EtOAc/hexanes)