Triethylamine → 1-Tert-butyl 3-methyl 1,2,5,6-tetrahydropyridine-1,3-dicarboxylate

Participants

Reaction Steps

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 solution, 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%)

Provenance & Evidence