反应详情

(R)-7-[3-tert-Butoxycarbonylamino-4-(2,4,5-trifluoro-phenyl)-butyryl]-3-trifluoromethyl-5,6,7,8-tetrahydro-imidazo[1,5-a]pyrazine-1-carboxylic acid 2a (0.275 g, 0.5 mmol) and 4 mL of N,N-dimethylformamide were added to the reaction tube. After stirring until 2a was dissolved, 1-chloroethyl cyclohexyl carbonate (0.124 g, 0.6 mmol), potassium iodide (0.0415 g, 0.25 mmol) and potassium carbonate (0.083 g, 0.6 mmol) were then added to the solution successively. Upon completion of the addition, the reaction tube was sealed up. The reaction mixture was reacted at 65° C. in an oil bath for 2 hours and monitored by thin layer chromatography until the disappearance of the starting materials, and then the oil bath was removed. After cooling to room temperature, 40 mL of water was added to the reaction tube. The reaction mixture was extracted with ethyl acetate (30 mL×3). The combined organic phase was washed with 30 mL of water and 30 mL of saturated brine successively. The combined organic phase was dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography to obtain the title compound (R)-7-[3-tert-butoxycarbonylamino-4-(2,4,5-trifluoro-phenyl)-butyryl]-3-trifluoromethyl-5,6,7,8-tetrahydro-imidazo[1,5-a]pyrazine-1-carboxylic acid (1-cyclohexyloxycarbonyloxy)-ethyl ester 38a (0.25 g, yield 69.4%) as a white solid.

1. dissolutionwas dissolved
2. additionUpon completion of the addition
3. customthe reaction tube was sealed up
4. customThe reaction mixture was reacted at 65° C. in an oil bath for 2 hours
5. customthe oil bath was removed
6. addition40 mL of water was added to the reaction tube
7. extractionThe reaction mixture was extracted with ethyl acetate (30 mL×3)
8. washThe combined organic phase was washed with 30 mL of water and 30 mL of saturated brine successively
9. dry with materialThe combined organic phase was dried over anhydrous magnesium sulfate
10. filtrationfiltered
11. concentrationconcentrated under reduced pressure
12. customThe resulting residue was purified by silica gel column chromatography