Imidazole → Tert-butyl 4-(2-iodoethyl)piperidine-1-carboxylate

Participants

Reaction Steps

To a solution of 1-(tert-butoxycarbonyl)-4-(2-hydroxyethyl)piperidine (458 mg, 2.0 mmol), Ph3P (785 mg, 3.0 mmol, 1.5 equiv.) and imidazole (204 mg, 3.0 mmol, 1.5 equiv.) in toluene (10 mL) was added I2 (761 mg, 3.0 mmol, 1.5 equiv.) at 0° C. The mixture was allowed to stand at room temperature overnight, before it was quenched with saturated Na2S2O3 solution. The product was extracted into CH2Cl2, and the organic layer was washed with brine and dried over Na2SO4. After concentration, the residue was purified by CC (SiO2, hexane/EtOAc 8:1, then 4:1). After removal of the solvents, 1-(tert-butoxycarbonyl)-4-(2-iodoethyl)piperidine (560 mg, 83%) was obtained as a colorless oil. 1H NMR (CDCl3, 400 MHz) δ 4.09 (br, 2H), 3.21 (t, 2H, J=7.2 Hz), 2.70 (t, 2H, J=12.0 Hz), 1.77 (q, 2H, J=7.2 Hz), 1.65 (d, 2H, J=12.8 Hz), 1.56 (m, 1H), 1.45 (s, 9H), 1.11 (m, 2H).

Provenance & Evidence