Tert-butyl 4-(1-ethoxy-1-oxopropan-2-yl)piperidine-1-carboxylate → Ethyl 2-(piperidin-4-yl)propanoate

A sample of tert-butyl 4-(1-ethoxy-1-oxopropan-2-yl)piperidine-1-carboxylate (1.4 g, 4.91 mmol) was dissolved in 4 M hydrogen chloride/dioxane (5 mL, 165 mmol) and stirred at RT for 2 h. At the conclusion of this period, the mixture was concentrated on a rotary evaporator and the resultant residue was treated with saturated NaHCO3 and then 1 M NaOH to bring the pH to 9. The mixture was extracted with EtOAc. The extract was washed with brine, dried (MgSO4) and concentrated to give ethyl 2-(piperidin-4-yl)propanoate (0.85 g, 93%). 1H-NMR (400 MHz, CDCl3) δ ppm 4.05-4.13 (2 H, m), 2.99-3.08 (2 H, m), 2.54 (2 H, td, J=12.09, 2.52 Hz), 2.16-2.25 (1 H, m), 1.75 (1 H, s), 1.57-1.66 (2 H, m), 1.52 (1 H, dt, J=12.90, 2.86 Hz), 1.09-1.22 (1 H, m), 1.21 (3 H, t, J=7.18 Hz), 1.07 (3 H, d, J=7.05 Hz).

1. concentrationAt the conclusion of this period, the mixture was concentrated on a rotary evaporator
2. additionthe resultant residue was treated with saturated NaHCO3
3. extractionThe mixture was extracted with EtOAc
4. washThe extract was washed with brine
5. dry with materialdried (MgSO4)
6. concentrationconcentrated

ORD-Eintrag

ord-0a5099200e21456cb2da8600bf1169cd

Quelldatensatz

uspto-grants-2013_01

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08354432B2