1-(1H-Imidazol-1-yl)ethanone → tert-Butyl 3-acetyl-4-oxopiperidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a solution of tert-butyl 4-oxopiperidine-1-carboxylate (6.00 g) in THF was added LDA (16 mL, 1 M) dropwise at −78° C. The mixture was stirred at −78° C. for 2 h. To this, a solution of N-acetylimidazole (3.50 g) in THF was added, and the reaction mixture was stirred at −78° C. for another 7 h, then quenched with 10 mL of ice-water and extracted with CH2Cl2 (50 mL×3). The combined organic phases were dried over anhydrous Na2SO4 and filtered. The filtrate was concentrated in vacuo and the residue was chromatographed with a silica gel column (eluting agent: 3:1 (v/v) PE/EA) to give the title compound as yellow oil (2.98 g, 41.00%), HPLC: 89.00%. The compound was characterized by the following spectroscopic data: MS (ESI, pos. ion) m/z: 242.4 (M+1); 1H NMR (400 MHz, CDCl3) δ: 1.47 (s, 9H), 2.13 (s, 3H), 2.28 (s, 1H), 2.44 (t, J=4.0 Hz, 2H), 3.58 (t, J=8.0 Hz, 2H), 3.97 (s, 2H) ppm.

Provenance & Evidence