[CH2:1]([N:5]1[CH:9]=[C:8]([C:10]2[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=2)[N:7]=[CH:6]1)[CH2:2][CH2:3][CH3:4].C([Li])CCC.CCCCCC.[I:27]I.[Cl-].[NH4+]>C1COCC1>[CH2:1]([N:5]1[CH:9]=[C:8]([C:10]2[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=2)[N:7]=[C:6]1[I:27])[CH2:2][CH2:3][CH3:4]To a solution of 1-butyl-4-phenylimidazole (4.0 g, 20 mmol) in 60 ml of anhydrous THF at −78° C. under nitrogen is added a solution of n-butyllithium in hexane (1.6M, 13.13 ml, 21 mmol, 1.05 eq.) dropwise. The resulting mixture is stirred at −78° C. for 1 h followed by dropwise addition of a solution of iodine (5.33 g, 21 mmol, 1.05 eq.) in 40 ml of THF. The resulting solution is stirred at −78° C. for 30 min. and then warmed to room temperature. Saturated ammonium chloride (30 mL) is added to quench the reaction. The resulting mixture is evaporated a reduced pressure to remove THF, extracted with ethyl acetate, washed with water and brine, dried over Na2SO4, filtered and evaporated. Purification by silica gel chromatography (hexanes/ethyl acetate, from 8:1 to 5:1) affords 5.73 g of 1-butyl-2-iodo-4-phenylimidazole. 1H NMR (400 MHz, CDCl3) δ 7.73 (2H, dd, J=1.2, 8.4 Hz), 7.36 (2H, m), 7.30 (1H, s), 7.24 (1H, m), 3.92 (2H, t, J=7.2 Hz), 1.79 (2H, m), 1.41 (2H, m), 0.98 (3H, t, J=7.2 Hz); MS (+VE) m/z 327 (M+1).
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