反应详情

Imidazole (310 mg, 4.40 mmol), iodine (440 mg, 3.5 mmol), and a solution of 2 (1 g, 2.98 mmol) in CH2Cl2 (2 mL) were added sequentially to a 0° C. solution of PPh3 (450 mg, 3.5 mmol) in CH2Cl2 (15 mL) and kept in the dark. After 2 h, the reaction mixture was quenched by adding 20% aq. Na2S2O3 (5 mL). The aqueous layer was extracted with CH2Cl2 (2×50 mL). The combined organic extracts were washed with brine (30 mL), dried over anhydrous Na2SO4, and the solvent was removed in vacuo. The residue was purified by careful column chromatography using 5% EtOAC/hexane to afford iodide 3 (1.25 mg, 92%). TLC: 10% EtOAc/hexane, Rf˜0.85; 1H NMR (CDCl3, 400 MHz) δ 7.67-7.62 (m, 4H), 7.45-7.35 (m, 6H), 3.67 (t, 2H, J=6.0 Hz), 3.41 (t, 2H, J=6.7 Hz), 2.03-1.93 (m, 2H), 1.72-1.64 (m, 4H), 1.04 (s, 9H).

1. customthe reaction mixture was quenched
2. additionby adding 20% aq. Na2S2O3 (5 mL)
3. extractionThe aqueous layer was extracted with CH2Cl2 (2×50 mL)
4. washThe combined organic extracts were washed with brine (30 mL)
5. dry with materialdried over anhydrous Na2SO4
6. customthe solvent was removed in vacuo
7. customThe residue was purified by careful column chromatography