反应详情

To a solution of tert-butyl 4-methyl-4-(3-oxopropoxy)piperidine-1-carboxylate (5.7 g, 21.01 mmol) in CH2Cl2 (150 mL) was added 1-(triphenylphosphoranylidene)propan-2-one (8.69 g, 27.3 mmol) and the resulting mixture was stirred at room temp for 16 h. Water was then added and the mixture was extracted with dichloromethane, dried (Na2SO4), filtered and concentrated. The residue was then purified by Biotage (5-40% EtOAc/hexane) to afford (E)-tert-butyl 4-methyl-4-((5-oxohex-3-en-1-yl)oxy)piperidine-1-carboxylate (5.25 g, 16.86 mmol, 80% yield) as colorless oil. 1H NMR (500 MHz, CDCl3) δ 6.85 (dt, J=16.1, 6.9 Hz, 1H), 6.15 (dt, J=16.0, 1.4 Hz, 1H), 3.79-3.66 (m, 2H), 3.47 (t, J=6.4 Hz, 2H), 3.12 (t, J=11.6 Hz, 2H), 2.49 (qd, J=6.5, 1.5 Hz, 2H), 2.29-2.26 (m, 3H), 1.73 (d, J=13.2 Hz, 2H), 1.47 (s, 9H), 1.46-1.39 (m, 2H), 1.18 (s, 3H). LCMS (M+Na)=334.3.

1. extractionthe mixture was extracted with dichloromethane
2. dry with materialdried (Na2SO4)
3. filtrationfiltered
4. concentrationconcentrated
5. customThe residue was then purified by Biotage (5-40% EtOAc/hexane)