反应详情

To a solution of tert-butyl 4-formylpiperidine-1-carboxylate (4.5 g, 21.10 mmol) in CH2Cl2 (50 mL) at 0° C. was added t-BuOK (3.08 g, 27.4 mmol) followed by MeI (3.96 mL, 63.3 mmol) at 0° C. The resulting mixture was stirred 30 min, and then warmed to room temp and stirred for 1.5 h. The reaction mixture was then poured into brine and the mixture was extracted with dichloromethane, dried (Na2SO4), filtered and concentrated. The residue was then purified by Biotage (0-20% EtOAc/hexane) to afford tert-butyl 4-formyl-4-methylpiperidine-1-carboxylate (1.8 g, 7.92 mmol, 37.5% yield) as colorless oil. 1H NMR (500 MHz, CDCl3) δ 9.48 (s, 1H), 3.71-3.66 (m, 2H), 3.19-3.05 (m, 2H), 1.93 (dt, J=13.7, 4.1 Hz, 2H), 1.47 (s, 9H), 1.46-1.37 (m, 2H), 1.10 (s, 3H). LCMS (M+H)=228.1.

1. stirringstirred for 1.5 h
2. extractionthe mixture was extracted with dichloromethane
3. dry with materialdried (Na2SO4)
4. filtrationfiltered
5. concentrationconcentrated
6. customThe residue was then purified by Biotage (0-20% EtOAc/hexane)