1-Methylimidazole → tert-butyl 4-hydroxy-4-(1-methyl-1H-imidazol-2-yl)piperidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

1-Methylimidazole (4.1 mL, 50 mmol) in dry tetrahydrofuran was treated with n-butyllithium (25 mL, 50 mmol) at room temperature and heated at 40° C. for 3 hours. The reaction was cooled to −78° C. and 4-oxo-piperidine-1-carboxylic acid tert-butylester (9.96 g, 50 mmol) added. The mixture was allowed to warm to room temperature, stirred for 6 hours the heated to 40° C. for an additional 3 hours. The reaction was cooled to room temperature, quenched with water and extracted with ethyl acetate. The organic phases were dried over magnesium sulfate, filtered and concentrated under reduced pressure. The crude material was recrystallized from methanol to provide the title compound (8.2 g, 84%) as white solid. 1H NMR (300 MHz, CDCl3) δ 1.45 (s, 9H), 1.8 (d, 2H, J=15 Hz), 2.1 (m, 2H), 3.3 (t, 3H, J=15 Hz), 3.8 (s, 4H), 6.8 (dd, 2H, J=9, 3 Hz); MS (DCI/NH3) m/e 282 (M+H)+.

Provenance & Evidence