Bromide ion → HCID 66833620, compound

Participants

Reaction Conditions

Reaction Steps

A solution of tert-butyl-4-[methoxy(methyl)-carbamoyl]-piperidine-1-carboxylate (5.04 g, 18.53 mmol), in tetrahydrofuran (50 mL) maintained under an atmosphere of nitrogen was cooled to 0° C. To this cold solution was added a THF solution of 4-butenylmagnesiun bromide (0.5 M in THF, 45 mL, 22.5 mmol) in a dropwise manner. The solution was stirred for 1 hour at 0° C. then allowed to warm to room temperature overnight. The resulting solution was poured into water, acidified to pH 3-4 with 1 N hydrochloric acid, and extracted with ethyl acetate (3×). The combined organic phase was washed with saturated aqueous sodium chloride, dried over anhydrous magnesium sulfate, filtered and concentrated in vacuo. Purification by flash column chromatography (silica gel, 0-25% ethyl acetate in heptane) gave tert-butyl-4-pent-4-enoylpiperidine-1-carboxylate as a colorless oil (4.37 g, 88%); 1H NMR (CDCl3, 300 MHz) δ 5.79 (m, 1H), 4.98 (m, 2H), 4.10 (m, 2H), 2.76 (t, J=11.5 Hz, 2H), 2.54 (m, 2H), 2.46 (tt, J1=11.5 Hz, J2=3.5 Hz, 1H), 2.32 (m, 2H), 1.78 (m, 2H), 1.48-1.58 (m, 2H) and 1.45 (s, 9H).

Provenance & Evidence