反应详情

To a cold (0° C.) solution of 1-tert-butyl 3-methyl 4-hydroxy-1,3-piperidine-dicarboxylate (1,64 g, 6.32 mmol), 4-dimethylaminopyridine (16.0 mg, 0.13 mmol), and triethylamine (2.64 mL, 19.0 mmol) in dichloromethane (25 mL) was added dropwise trifluoroacetic anhydride (1.12 mL, 7.91 mmol). The reaction mixture was stirred at room temperature for 40 hrs. The reaction was quenched with 10% K2CO3 solurtion, extracted with CHCl3. The separated organic phase was washed with brine, dried over MgSO4, filtered and evaporated under reduced pressure. The crude product was purified by silica gel column chromatography (hexane:ethyl acetate=5:1) to give 1-tert-butyl 3-methyl 5,6-dihydro-1,3(2H)-pyridinedicarboxylate as a pale yellow oil. (707.4 mg, yield 46%)

1. customThe reaction was quenched with 10% K2CO3 solurtion
2. extractionextracted with CHCl3
3. washThe separated organic phase was washed with brine
4. dry with materialdried over MgSO4
5. filtrationfiltered
6. customevaporated under reduced pressure
7. customThe crude product was purified by silica gel column chromatography (hexane:ethyl acetate=5:1)