反应详情

To a solution of 2-allylpyrrolidine-1,2-dicarboxylic acid 1-tert-butyl ester 2-methyl ester (25.0 g) in tetrahydrofuran (125 ml) cooled to 0° C. was added dropwise borane-tetrahydrofuran complex (1.0M tetrahydrofuran solution, 105 ml) over 30 minutes, and the mixture was stirred at the same temperature for 2.5 hours. To the reaction mixture was added dropwise additional borane-tetrahydrofuran complex (1.0M tetrahydrofuran solution, 11 ml), and the mixture was stirred at the same temperature for 50 minutes. To the reaction mixture was added dropwise water (180 ml) over 30 minutes and added sodium peroxoborate 1 hydrate (12.0 g) in small batches. The mixture was warmed to room temperature and stirred overnight, and then thereto was added water (500 ml). The mixture was extracted with ethyl acetate (600 ml). The separated organic layer was washed with 20% aqueous sodium thiosulfate solution (600 ml) and saturated aqueous sodium chloride solution. The separated aqueous layer was extracted with ethyl acetate (300 ml, 200 ml) twice. The combined organic layer was dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography (eluent: n-hexane/ethyl acetate=2/1 to 1/1) to give the titled compound (17.4 g).

1. stirringthe mixture was stirred at the same temperature for 50 minutes
2. stirringstirred overnight
3. extractionThe mixture was extracted with ethyl acetate (600 ml)
4. washThe separated organic layer was washed with 20% aqueous sodium thiosulfate solution (600 ml) and saturated aqueous sodium chloride solution
5. extractionThe separated aqueous layer was extracted with ethyl acetate (300 ml, 200 ml) twice
6. dry with materialThe combined organic layer was dried over anhydrous sodium sulfate
7. concentrationconcentrated under reduced pressure
8. customThe resulting residue was purified by silica gel column chromatography (eluent: n-hexane/ethyl acetate=2/1 to 1/1)