反应详情

6-[3-(tert-Butyldimethylsiloxy)cyclopent-1-enyl]-2-cyclopropyl-7-fluoro-5-methyl-1,3-benzoxazole-4-carbonitrile (I-304) (275 mg, 0.67 mmol) was dissolved in tetrahydrofuran (6 ml), and at 0° C., tetra-n-butylammonium fluoride (1.0 M tetrahydrofuran solution, 1.0 ml, 1.0 mmol) was added. After stirring at room temperature under nitrogen atmosphere for 16 hours, aqueous saturated ammonium chloride solution was added to the solution at 0° C., followed by stirring at the same temperature for 5 minutes. This was extracted three times with ethyl acetate. The organic layers were combined, washed with saturated brine, and dried over anhydrous sodium sulfate. The insoluble matter was separated by filtration, the solvent was evaporated away, and the resulting residue was purified by middle-pressure liquid chromatography (eluent, n-hexane:ethyl acetate=1:1, v/v) to obtain the entitled compound (91 mg, 46%) as a white solid.

1. stirringby stirring at the same temperature for 5 minutes
2. extractionThis was extracted three times with ethyl acetate
3. washwashed with saturated brine
4. dry with materialdried over anhydrous sodium sulfate
5. customThe insoluble matter was separated by filtration
6. customthe solvent was evaporated away
7. customthe resulting residue was purified by middle-pressure liquid chromatography (eluent, n-hexane