反应详情

DBU (2.99 ml; 20.06 mmol; 1.10 eq.) was dissolved in DMF (25 ml) and put under nitrogen atmosphere. 3-Cyclopentyl-3-oxo-propionic acid ethyl ester (Pharmacore, 3.695 g; 20.06 mmol; 1.10 eq.) was added to the mixture and it was stirred for 15 min. Then a solution of 1-azido-2-fluorobenzene, prepared according to Platz, M. S. et al. J. Org. Chem. 1989, 54, 5938-5945, (2.5 g; 18.23 mmol; 1 eq.) in DMF (5 mL) was added dropwise to the solution at room temperature. The mixture was stirred at 90° C. for 2 hours. Water (50 mL) was added to the cooled reaction mixture and the aqueous layer was extracted with EtOAc (3×50 mL). Combined organics were washed with water and brine, dried over MgSO4 and concentrated under vacuum affording the title compound as a yellow oil. It was used in the next step without further purification. LC/MS (Method B): 304.2 (M+H)+.

1. stirringThe mixture was stirred at 90° C. for 2 hours
2. extractionthe aqueous layer was extracted with EtOAc (3×50 mL)
3. washCombined organics were washed with water and brine
4. dry with materialdried over MgSO4
5. concentrationconcentrated under vacuum