反应详情

194 mg of tert-butyl 4-(3-bromo-2-fluorobenzoyl)piperazine-1-carboxylate was dissolved in 5.0 ml of tetrahydrofuran, and 1.25 ml of a solution of isobutylmagnesium chloride in tetrahydrofuran (2.0 M) was added thereto at −78° C. After stirring at the same temperature for 2 hours, 0.39 ml (5.0 mmol) of N,N-dimethylformamide was added thereto. The resulting mixture was stirred at the same temperature for 30 minutes and further stirred at 0° C. for 30 minutes. To the reaction mixture was added saturated ammonium chloride, and the mixture was extracted with chloroform. The organic layer was washed with brine and then concentrated. The residue was purified by a silica gel column chromatography (eluent: hexane/ethyl acetate=9/1 to 1/1) to give the title compound.

1. customat −78° C
2. stirringThe resulting mixture was stirred at the same temperature for 30 minutes
3. stirringfurther stirred at 0° C. for 30 minutes
4. extractionthe mixture was extracted with chloroform
5. washThe organic layer was washed with brine
6. concentrationconcentrated
7. customThe residue was purified by a silica gel column chromatography (eluent: hexane/ethyl acetate=9/1 to 1/1)